November 10 2006. The Church dedicated to St. James-the-less in the middle of the A13 road at Hadleigh was visited today for comparison of the London Clay concretion colours with the northern Essex church visited a week before. They were both largely Norman structures but at Hadleigh the stone was largely transported over the Thames from Kent in the early exciting reign of King Stephan (c.1140); probably as a secular defense measure by the church authorities. The eastern and western ends of the church were respectively repaired with the same and some new stone in 1854 (following collapse of the semicircular apse) and 1949 (following 1934-45 aerial bombing). A greater obscuration of the original fabric is due to the construction of a vestry in 1928 outside the northwest nave and a small wooden south porch in the 18th Century. There is no external tower only a wooden one on interior nave posts.
The first circuit of the exterior showed only one possible London Clay concretion in the lower two metres of all the old walls. The second more careful circuit provided a sample of colour measurements from ten stones and during a restudy of these particular stones on a third circuit this sample was reduced to 16 colours determined from four stones near the eastern ends of the nave and 8 colours determined from four less clearly London Clay concretions in the south wall of the chancel and the S.W. region of the nave beyond the porch. That corner included a probable glacial erractic of silica cemented, non-Cretaceous sandstone, with dimensions of 450 mm by 450mm that were larger than the Cretaceous sandstones and siltstones blocks obtained from Kent. There were also a few somewhat smaller slabs of ferricrete (iron oxide cemented flint gravel) in the south and west nave.
The largest stone of clearly London Clay origin had exposed dimensions of 220 mm by 180 mm shaped by splitting a concretion along prismatic calcite veins of 5 mm maximum half-thickness flanked on both sides by dark grey to moderate red, originally pyritic joint surfaces (5R 4/1-5R 4/4). The matrix of finer-grained calcite cemented clay graded from this colour, through paler browns and oranges, to a worn rather than a bored exterior weathered yellowish grey (5Y 7/2). Adding what appear to be beach-worn pebbles of the claystone matrix, the average colour of 16 studied spots is 6.56 YR 5.813/3.500 of the Munsell Co. system (i.e. roughly yellowish orange). The provinance is not the same as Broomfield Church as the veins were thicker and more pyritic but it is still unclear whether it represents division A3 of the Reculver-Herne Bay coast in Kent, or the division D/E boundary septaria which can still be found in Hadleigh Cliffs below and east of the subsequently built castle. The sea-worn appearance of some of the stones is of course opposed to that idea since Hadleigh Castle has old marshland separating it from the sea. But if the Kentish stones were landed at the more convenient port of Leigh and had their oyster-shell mortar added there i.e. even now a few whole oyster shells can be seen in the apse) then this objection is overcome. The more doubtful additional 8 colour determinations from four rather less weathered, silty-looking angular stones averaged 1.25 Y 5.750/2.875, which is roughly yellowish to olive grey. If it is reasonable to add them the general average from Hadleigh Church only shifts to 8.12 YR 5.792/3.292, which is yellowish orange. I suspect that the whole modern oyster shells used to make the mortar between the Kentish ragstone and other imported superior building stones came from London Clay shorelines on both sides of the Thames estuary. Some septaria were therefore collected with the future mortars up until the end of Church building with the reformation. It is therefore worth looking for London Clay concretions and recording their weathered colours etc in South Essex walls which are not supposed to contain them in published descriptions. Conversely when the London Clay concretions are common enough to have been noticed by visitors with more general interests, then they probably came from specific sites along the Essex or Kent coastline where they were gathered as building stones in an earlier period ending around 1200. There alternative perspective might be that a few concretions were like the Roman brick and tile fragments also seen in small numbers at Hadleigh Church and most south Essex churches, and came from the use of Saxon or Roman buildings as quarries in stone-poor Essex lands. A third idea, which I think is less likely, is that the insitu septaria seen now in fields such as those near Hadleigh Castle, were formerly gathered as additional building stones from each manor. Much will depend on how stable London Clay slopes were in ancient times when ploughing and excavation work was less easy than in modern times. However, it is relatively easy to test this local hypothesis by comparing the colours and weathered textures of church concretions with those found locally today.
Saturday, November 25, 2006
Thursday, November 16, 2006
Angel Wing’s at Broomfield
November 7 2006. During the visit to Broomfield Church in Essex last Friday, it was noticed that one cluster of London Clay concretions in the nave contained borings by the modern marine worm Poydora ciliata Johnstone not seen elsewhere at convenient elevations in the walls and associated in one 130 mm by 80 mm stone with 6 mm diameter bivalve borings and insitu shells. In eastern North America, this type of bivalve or clam are given the name Angel Wing, more by comparison with the six and elongated wing development reviewed in Isaiah 6 v.2 than more speculative Christmas card illustrations with two spread wings like a bird. The bivalves in the wall building stone had bored in when it was on the lower or middle foreshore of Essex or North Kent, with rough radial ribs extending to a diameter of 6 mm at the working face and a delicate concentric ornament of growth ridges extending towards the entrance for the shell length of at least 15 mm before the stone was collected in Roman, Saxon or earliest Norman times. A complete and fully investigated shell would probably have an additional pair of small shelly plates filling the gape between the valves at the working face, or alternatively a fused similar folded structure there. It was not clear to me which species was present as juvenile and partly hidden shells in the church. Bearing in mind the age of the wall and the lack of evidence of repairs at that spot it is unlikely that the American species Petricola pholadiformis Lamarck [False Angel Wing] needs to be carefully separated from the unrelated homeomorphic English Native species Barnea candida (L.) [White Piddock] allied to the American B. truncata say [Small Angel Wing]. Petricola was first noticed in the River Crouch Estuary of Essex in July 1890 (see N. Tebble British Bivalve Seashells (1966) p. 126). However there is also a smaller English species, which although looking wider than those in the wall are are, is known from the Kent coast and provides an alternative identification. This is Barnea parva (Pennant) [Little Piddock]. There are also larger species Pholoas dactylus L. [Common Piddock] and Zirfaea crispata (L.) which also bore into rocks in southern England but which look somewhat different to the church shells.
The host rock would once have been a large concretion embedded in the London Clay below and probably partly covered by modern mud or sand above. It was then split along natural joints and a few thin septarian calcite veins either by the sea, during collection or transport or more likely just before building of the nave. One can see that the wall consists of a regular size and shape of the stones, with similar-looking fragments of probably the same original concretion placed next to each other, and the Polydora bored surfaces concentrated at the one spot in the whole wall. Unlike many other Essex walls there are no large intact concretions, and no thick-veined or open-veined concretions present. Elsewhere in the nave and older part of the Chancel there are concretions split along sepatarian calcite veins with a half-thickness of up to 4 mm and more iron-stained prisms at the edge nearest to the calcite claystone matrix. But they are not common enough to be seen with the bored material and this suggests a source in the division B, or middle London Clay of Kent or Essex, where septarian veins are thin and sparse. However, since both veined and unveined concretions are termed septaria in archaeological accounts of Essex it is reasonable to use that name for London Clay concretions regardless of vein frequency. This stratigraphical deduction implies that the concretions were not gathered from the subsequently suitable habitat for boring bivalves in the Crouch estuary or indeed the Roach and on the Thames at Southend. These are all upper London Clay foreshore sites, termed division C to E, in which even a small sample of concretions soon shows some thicker and or more open septarian veins. At Southend one can certainly find Polydora borings but often they and other marine animal traces are so common as to make the original surface features of the concretion hard to observed. This is particularly the case with museum specimens of division B dredged-up from subtidal environments at Clacton and Whitstable in early Victorian times. In all probability this mode of collection was not known to people in Roman or Saxon times and the resulting building stones at Broomfield look as if they came from a muddy foreshore in which the sedimentation rate was fast enough to limit the growth of the oysters sometimes seen on concretions in churches.
A more direct method of working on the provenance of the bored concretions is to record the colours of the pre-collection weathering zones by direct comparison with the Geological Society of America Rock-Color chart held up in the same illumination. Holes cut in a grey cardboard (N7) are placed in front of each spot on the stones. Weathering in the wall mainly has the effect of exfoliating the outer layers and increasing the lightness value. Probably this weathering was limited by a covering of limewash mortar until the Victorian era. The stones display bright colours developed in Pleistocene subsoils and later to greys modified in deoxygenated foreshore muds.
Much time at Broomfield was spent on measuring 70 individual coloured areas on typical concretions at the S.W. corner of the nave another 47 in and directly around the bored concretions. Using the conventions of the Munsell Color Company these two sets of observations have slightly different averages equal to 0.42 Y 6.314/3.286 in the S.W. corner and to 9.57 YR 6.149/2.660 in the unusual area including borings. In the rough terminology of American words the typical Broomfield concretions average as a dusky yellow and the abnormal area of the wall with borings as pale yellowish brown. At the times I noticed that one set of Plydora borings were in a greyish orange (10YR 7/4) surface, around an unusually dark core of moderate brown (5YR 4/4) which also formed a hard cortex to an adjacent unbored ellipsoidal concretion with a soft pale orange interior (10 YR 8/6). The adjacent fragment with the bivalves in it showed a similar pale orange exterior (10 YR 7/4) which had exfoliated in the 5 mm thick cortex of the Polydora borings to show the more original colour to be greyish orange pink (5 YR 7/2). Previous experience suggests that this layer was once composed of hydrogen sulphide developed in foreshore muds and around empty Ploydora borings, and has presumably become lighter by oxidation in the dry wall. Inside this cortex the bivalve concretion had a very pale orange (10 YR 8/2) exfoliated matrix. Elsewhere in the wall darker brown matrix and locally red stained joints seen in the abnormal area were less conspicuous and this is reflected in the average colourations subsequently calculated.
The host rock would once have been a large concretion embedded in the London Clay below and probably partly covered by modern mud or sand above. It was then split along natural joints and a few thin septarian calcite veins either by the sea, during collection or transport or more likely just before building of the nave. One can see that the wall consists of a regular size and shape of the stones, with similar-looking fragments of probably the same original concretion placed next to each other, and the Polydora bored surfaces concentrated at the one spot in the whole wall. Unlike many other Essex walls there are no large intact concretions, and no thick-veined or open-veined concretions present. Elsewhere in the nave and older part of the Chancel there are concretions split along sepatarian calcite veins with a half-thickness of up to 4 mm and more iron-stained prisms at the edge nearest to the calcite claystone matrix. But they are not common enough to be seen with the bored material and this suggests a source in the division B, or middle London Clay of Kent or Essex, where septarian veins are thin and sparse. However, since both veined and unveined concretions are termed septaria in archaeological accounts of Essex it is reasonable to use that name for London Clay concretions regardless of vein frequency. This stratigraphical deduction implies that the concretions were not gathered from the subsequently suitable habitat for boring bivalves in the Crouch estuary or indeed the Roach and on the Thames at Southend. These are all upper London Clay foreshore sites, termed division C to E, in which even a small sample of concretions soon shows some thicker and or more open septarian veins. At Southend one can certainly find Polydora borings but often they and other marine animal traces are so common as to make the original surface features of the concretion hard to observed. This is particularly the case with museum specimens of division B dredged-up from subtidal environments at Clacton and Whitstable in early Victorian times. In all probability this mode of collection was not known to people in Roman or Saxon times and the resulting building stones at Broomfield look as if they came from a muddy foreshore in which the sedimentation rate was fast enough to limit the growth of the oysters sometimes seen on concretions in churches.
A more direct method of working on the provenance of the bored concretions is to record the colours of the pre-collection weathering zones by direct comparison with the Geological Society of America Rock-Color chart held up in the same illumination. Holes cut in a grey cardboard (N7) are placed in front of each spot on the stones. Weathering in the wall mainly has the effect of exfoliating the outer layers and increasing the lightness value. Probably this weathering was limited by a covering of limewash mortar until the Victorian era. The stones display bright colours developed in Pleistocene subsoils and later to greys modified in deoxygenated foreshore muds.
Much time at Broomfield was spent on measuring 70 individual coloured areas on typical concretions at the S.W. corner of the nave another 47 in and directly around the bored concretions. Using the conventions of the Munsell Color Company these two sets of observations have slightly different averages equal to 0.42 Y 6.314/3.286 in the S.W. corner and to 9.57 YR 6.149/2.660 in the unusual area including borings. In the rough terminology of American words the typical Broomfield concretions average as a dusky yellow and the abnormal area of the wall with borings as pale yellowish brown. At the times I noticed that one set of Plydora borings were in a greyish orange (10YR 7/4) surface, around an unusually dark core of moderate brown (5YR 4/4) which also formed a hard cortex to an adjacent unbored ellipsoidal concretion with a soft pale orange interior (10 YR 8/6). The adjacent fragment with the bivalves in it showed a similar pale orange exterior (10 YR 7/4) which had exfoliated in the 5 mm thick cortex of the Polydora borings to show the more original colour to be greyish orange pink (5 YR 7/2). Previous experience suggests that this layer was once composed of hydrogen sulphide developed in foreshore muds and around empty Ploydora borings, and has presumably become lighter by oxidation in the dry wall. Inside this cortex the bivalve concretion had a very pale orange (10 YR 8/2) exfoliated matrix. Elsewhere in the wall darker brown matrix and locally red stained joints seen in the abnormal area were less conspicuous and this is reflected in the average colourations subsequently calculated.
Saturday, November 11, 2006
Broomfield Church, Essex (Part 1)
November 3 2006. The parish church of Broomfield, originally dedicted to St. Leonard and now to St. Mary the Virgin, lies on the ancient route from Bury St. Edmunds, via Braintree and Ingatestone, to Roman London. The parish resembles Prittlewell and Sutton Hoo in evidently being an early Anglo-Saxon administrative center, with archaeological evidence of prosperous graves situated away from the church, which was presumably avoided in the Pagan era. But perhaps the burial of people around churches is a modern custom developed when the church took over administrative functions and in other parishes, such as Ingatestone, the site of the moot and gathered tithes? I visited Broomfield today to see whether it resembled Ingatestone and Braintree Churches in showing a large stone of Saxon-era significance along the road, and to study the Eocene London Clay concretions present in the walls of many older Eastern Essex churches and castles. According to the Inventory of the Historical Monuments of Essex, volume 2, by the Royal Commission of Historical Monuments they are erroneously described as “lumps of brown boulder clay” embedded in most parts of the church with “flints and short courses of Roman Brick.” The historical dating in their account is doubtless more correct and shows that the round early 12th Century west Tower lacking the London Clay concretions was added to their concentration in the south wall of the Nave and western Chancel built in the 11th Century (i.e. perhaps Saxon or earlier Norman). The Tower was presumably built with the similar one at Great Leighs, 6 km to the N.E. and off the old road, by visiting builders who employed the superior building stone of flints for their work, and perhaps brought it with them to both sites. However when the church was enlarged to the east and north in the 15th Century and modern period the London Clay concretions were used again, and this was also the case in the “modern” South Porch of the Royal Commissioners. One can easily imagine parts of the old wall being removed to make extensions and then that stone being used again partly to save transport costs and partly to match the colour and texture of the existing exterior. However, the part of the northern walls added since the Commissioners Report, which we would term new if modern is defined as post-1714, has much the same appearance without including any London Clay or Roman materials in it.
I intend to add a technical account of the colour and fossil content of these particular London Clay concretions in the Nave as a later entry to the blog. The typical material was studied on the west side of the porch among Roman Bricks or tiles. One of the Roman bricks was easily measured on the S.W. corner quoin there as having square dimensions of 290 mm by 290 mm, with a variable thickness of 35 to 45 mm, and having a no interior black reduction band on display. These were, however, seen in smaller fragments of probable Roman tile in the main part of the Nave walls. Flints with a white patina and various rather scarce sandstones were also present, but it is London Clay concretions that dominate and is the “stone that is weathered a strong mustard yellow” in the description by Norman Scarfe (A Shell Guide to Essex, Fuber and Fuber, London). Probably these concretions and the Roman Bricks are derived from an earlier Saxon structure on the site, which may have been built along the route when St. Edmunds boy transported to London or in the remote period of the Saxon gravegoods. Prittlewell Church certainly existed, and was modified, around the time of the early 7th Century burials, without them being shifted towards it. What I did notice was that a large stone was indeed present as expected in the Nave wall at Broomfield, and projecting about 400 mm south from it. It consists of 90 mm long, white and other irregular flints cemented by hard ferricrete or perhaps even silica, into a Puddingstone (sensu Royal Commission, but not the Hertfordshire Puddingstone of geologist’s). The resulting boulder has a diameter of 0.4 m and a length of at least twice that extending to secure it in the Nave wall just west of the 14th Century S.E. Nave window. Perhaps it had functions at that time as a table for alms given to the poor, or as a mounting block for horse riders on a lower ground level? The various studied descriptions of the Church do not note it at all. However, originally it may have been where tithes and manorial obligations were made in a moot operating in the northern half of Chelmsford Hundred, in a similar way to the Kings Hill gathering at Rayleigh and at the Ingatestone.
I intend to add a technical account of the colour and fossil content of these particular London Clay concretions in the Nave as a later entry to the blog. The typical material was studied on the west side of the porch among Roman Bricks or tiles. One of the Roman bricks was easily measured on the S.W. corner quoin there as having square dimensions of 290 mm by 290 mm, with a variable thickness of 35 to 45 mm, and having a no interior black reduction band on display. These were, however, seen in smaller fragments of probable Roman tile in the main part of the Nave walls. Flints with a white patina and various rather scarce sandstones were also present, but it is London Clay concretions that dominate and is the “stone that is weathered a strong mustard yellow” in the description by Norman Scarfe (A Shell Guide to Essex, Fuber and Fuber, London). Probably these concretions and the Roman Bricks are derived from an earlier Saxon structure on the site, which may have been built along the route when St. Edmunds boy transported to London or in the remote period of the Saxon gravegoods. Prittlewell Church certainly existed, and was modified, around the time of the early 7th Century burials, without them being shifted towards it. What I did notice was that a large stone was indeed present as expected in the Nave wall at Broomfield, and projecting about 400 mm south from it. It consists of 90 mm long, white and other irregular flints cemented by hard ferricrete or perhaps even silica, into a Puddingstone (sensu Royal Commission, but not the Hertfordshire Puddingstone of geologist’s). The resulting boulder has a diameter of 0.4 m and a length of at least twice that extending to secure it in the Nave wall just west of the 14th Century S.E. Nave window. Perhaps it had functions at that time as a table for alms given to the poor, or as a mounting block for horse riders on a lower ground level? The various studied descriptions of the Church do not note it at all. However, originally it may have been where tithes and manorial obligations were made in a moot operating in the northern half of Chelmsford Hundred, in a similar way to the Kings Hill gathering at Rayleigh and at the Ingatestone.
Friday, November 10, 2006
Winter arrives in Southend.
November 2 2006. Media reports from a lightship in the southern North Sea at 4 Hrs. G.M.T. indicate that the drop in the temperature of my experimental seawater tank was able to cause sinkings due to a rise in barometric pressure after variable pressure in a gale. On the morning of October 31 the temperature was still 58½°F (14.7°C) and the pressure of 100.8 KPa was associated with a SW by S wind of force 7. Next morning the temperature had dropped to 52½°F (11.4°C), the pressure was 102.0 KPa and the cold wind was force 6 from the northwest. This morning the wind had moderated here but was reported offshore as force 5 from the N.N.W. at a pressure of 103.1 KPa. The tank water temperature had declined further to 48°F (8.9°C) causing the 8th of a set of 10 dry fallen Pinus pineaster Aiton cones to sink apex-up in the night, after about 113.0 days (length 104 mm, diameter 37 mm). Most of the sinkings due to the sudden arrival of winter took place on November 1st. During the first cold night a brown decayed 66 mm diameter apple sank in freshwater after about 21.5 days and was moved to seawater to see how much longer it would float in denser water with salt ions presumably diffusing into largely flooded, brown decayed flesh. The cork present in a bucket of seawater sank after about 2056.7 days, with the surface originally punctured by the corkscrew predictably at the base. The angle of tilt of this cylinder (46 mm by 23 mm) was 45 degrees. At 15 Hrs. the ash log in the same recently illustrated apple bucket sank horizontally after 31.0 days. It had more elongated dimensions (200 mm by 60 mm). At around 17 Hrs. a probable curlew secondary wing feather sank entirely intact and vertical after 58.2 days (length 119 mm by 18 mm vane width and 2.6 mm maximum calamus diameter). Of these only the cork qualifies as a long-term floatation defining seasonal singularities in sinkings reviewed from 37 cases in The Drifting Seed vol. 12 (no.1), p9-10. Since that report a charcoal sank on July 16 after 1548 days at 17.8°C and 102.6 KPa and now the cork as noted above. Usually the annual cooling event is from November 14 to 19, but there was one previous sinking at this time of year in my data set. This was a pumice stone sunk by 7 Hrs. G.M.T. on November 2 2001 at a higher temperature (13.9°C) and pressure (104.0 KPa).
These events took place during a period of low actual and predicted high tides at Westcliff to Chalkwell beaches. The morning strandline of October 31 was predicted to be 1.8 m above mean sea level at 5.27 Hrs. and was briefly studied at Westcliff around 13 Hrs. The strandline had by then been modified by sand blowing along it from the west but was still well defined by strings of Fucus, Zostera and reed tops bound into spiral bunches. Whiteweed (Serturlia) was present from the lower intertidal zone exposed to the gales. Paired Mytilus and Cerastoderma shells had stranded. A few green Halimone leaves were also observed. They would have been able to remain floating since the tides reached their higher level on the intertidal zone around October 25.
Many Halimone leaves were deposited with Fucus, twigs, gull feather and seawater on the Westcliff promenade by the O.44 Hr. G.M.T. tide of October 23. The predicted height of this tide was 2.7 m above mean sea-level but the debris was much higher than that and the waves probably removed the Halimone leaves from insitu plants at that time. It also rained later that day and not much since then, so that the buoyant yellow-red apple stranded with a few leaves on October 31 had probably also been in the sea for a week. This stranded apple was damaged on one side, probably by falling from the tree rather than by stranding on weed and sand. It was collected and refloated in seawater on the beach and has remained floating in the tanks, stalk-up since then.
The visit to Chalkwell beach after the similarly low morning tide of November 1st showed that a live Brent Goose had returned from Siberia and was swimming in a tide that was only slowly retreating from a poorly defined strandline. Presumably the north wind had prevented Fucus and other buoyant materials from stranding on the south-facing beach. Even the algal concentrations on the west side of breakwaters may have arrived earlier with the westerly gales and similarly low high tides. However, the new patches of gravel near the top of the wet part of the beach sand were associated with a few gull and oyster catcher feathers, which had stranded recently.
On land the birds now seem to go about in one flock; including one Wren, Blue Tits, a pair of Blackbirds, House Sparrows and even an aggressive Robin. Perhaps the gardens are normally now so full of parking lots and decking that the birds need to protect each other from cats and hawks by moving together from one exposed bird table to the next? Before the cold wind, and as recently as October 27th (and again on Nov 9th) there were more solitary visits from the attractive large Red Admiral Butterfly Vanessa atalanta. At 9 Hrs. G.M.T. on October 25 a bold large fox nearly walked into me in the urban setting of Lansdowne avenue Chalkwell, near the busy A13 road. It decided it would retreat behind a parked car before going on over the street, which was not displaying any garbage, bags that day. As far as the leaf fall is concerned, one ash tree has now (November 2) lost all of them while the one next to it resembles the local Hawthorne and oak in still having an insitu and largely green leaf displays. Frogs still sing in the day and hedgehogs still scream in the night last week.
These events took place during a period of low actual and predicted high tides at Westcliff to Chalkwell beaches. The morning strandline of October 31 was predicted to be 1.8 m above mean sea level at 5.27 Hrs. and was briefly studied at Westcliff around 13 Hrs. The strandline had by then been modified by sand blowing along it from the west but was still well defined by strings of Fucus, Zostera and reed tops bound into spiral bunches. Whiteweed (Serturlia) was present from the lower intertidal zone exposed to the gales. Paired Mytilus and Cerastoderma shells had stranded. A few green Halimone leaves were also observed. They would have been able to remain floating since the tides reached their higher level on the intertidal zone around October 25.
Many Halimone leaves were deposited with Fucus, twigs, gull feather and seawater on the Westcliff promenade by the O.44 Hr. G.M.T. tide of October 23. The predicted height of this tide was 2.7 m above mean sea-level but the debris was much higher than that and the waves probably removed the Halimone leaves from insitu plants at that time. It also rained later that day and not much since then, so that the buoyant yellow-red apple stranded with a few leaves on October 31 had probably also been in the sea for a week. This stranded apple was damaged on one side, probably by falling from the tree rather than by stranding on weed and sand. It was collected and refloated in seawater on the beach and has remained floating in the tanks, stalk-up since then.
The visit to Chalkwell beach after the similarly low morning tide of November 1st showed that a live Brent Goose had returned from Siberia and was swimming in a tide that was only slowly retreating from a poorly defined strandline. Presumably the north wind had prevented Fucus and other buoyant materials from stranding on the south-facing beach. Even the algal concentrations on the west side of breakwaters may have arrived earlier with the westerly gales and similarly low high tides. However, the new patches of gravel near the top of the wet part of the beach sand were associated with a few gull and oyster catcher feathers, which had stranded recently.
On land the birds now seem to go about in one flock; including one Wren, Blue Tits, a pair of Blackbirds, House Sparrows and even an aggressive Robin. Perhaps the gardens are normally now so full of parking lots and decking that the birds need to protect each other from cats and hawks by moving together from one exposed bird table to the next? Before the cold wind, and as recently as October 27th (and again on Nov 9th) there were more solitary visits from the attractive large Red Admiral Butterfly Vanessa atalanta. At 9 Hrs. G.M.T. on October 25 a bold large fox nearly walked into me in the urban setting of Lansdowne avenue Chalkwell, near the busy A13 road. It decided it would retreat behind a parked car before going on over the street, which was not displaying any garbage, bags that day. As far as the leaf fall is concerned, one ash tree has now (November 2) lost all of them while the one next to it resembles the local Hawthorne and oak in still having an insitu and largely green leaf displays. Frogs still sing in the day and hedgehogs still scream in the night last week.
Thursday, November 09, 2006
Floatation of Tilia leaves in seawater
October 25 2006. According to various botanical books the structure of a deciduous large leaf consists of a waxy epitheluim which keeps gases out except via pores (stomata) on the lower paler green surface. These stomata close to prevent water from moving through them, and are adjacent to a lower layer of cells between an air cavity space termed the spongy mesophyll. The upper half of the leaf also contains some air between more continuous palisade cells, and had a darker brown colour between the supporting veins on a yellow fallen Tilia which sank first. All of them looked more transparent and yellow near the black veins and more brown and opaque on the upper surface between the veins when later dried-out. But it is still rather unclear why some of these yellow fallen leaves sank quicker than in those in the green parent condition and the others much longer despite being more damaged. Probably the larger air spaces contract and the replacement of the water held inside the palisade cells by more salty water that prevents or slows their decay to producing brown opaque bacterial/fungal material. Certainly the experimentally sunk leaves did not look more altered. It must therefore be presumed that the uniform brown colouration of stranded leaves seen today (Oak and various others not Tilia) developed on land, or during drying on mudflats etc..
Tilia leaf
The example of a test of leaves was started on October 17 with the collection of 10 yellow fallen and 10 picked green Tilia leaves at Braintree (west of the southern end of New Street and fallen on to a parking lot). After five hours in a plastic bag they were floated in all the recently illustrated buckets and tanks of seawater. A brown set collected on January 30 2001 was dried between newspapers before being similarly tested 26 days later.
The sinking of these leaves in buckets and tanks did not appear to depend on water quality. It involved estimation of times when they sink in the night, or between observations. My method has been to stay up for the first and last sinkings of a set, if sinking looked eminent, and not worry too much if the sinkings around the average had to be roughly estimated. Usually I have studied undried leaves so I was not satisfied with the seven previous Tilia times from dried brown and decayed material. The results for the tree sets are as follows (latest at 15°C):
Brown (7) Av. 6.67 days (range 0.847-10.124)
Yellow (10) Av. 2.1165 days (range 0.811-6.679)
Green (10) Av. 2.178 days (range 1.654-2.694)
The average dimensions of the green set were 85.9 mm by 78.5 mm width on the leaf itself, and 126.8 mm inclusive of the peteole or stem. The largest actually sank fist and had corresponding dimension of 128 mm by 123 mm, and 175 mm total length. The yellow set provides a more natural sampling of the leaf fall and averaged 67.0 mm by 61.8 mm width, with a total length of 96.0 mm. The largest leaf was the last to sink, probably because the peteole was shorter than the penultimate sinking of one with the same overall length of 130 to 131 mm in 3.047 days. These two yellow leaves respectively measured 80 by 68 mm width and 93 by 74 mm width on the leaf itself. Where the leaf was longer on the sides than along the central vein I measured the later, and where damage to the tip had occurred I estimated this length. The damaged leaves actually had averaged times and were relatively small, but the two longer floating yellow leaves did look thinner and paler on the upper surface when finally dried-out.
Incidentally, I am not sure which species this downtown Braintree belongs too. Judging from the larger leaf size, it would be Tilia platyphyllos Scopoli; but the hairs on the lower side of the leaf were confined to vein branches as in the hybrid between it and the Nature north Essex Tilia cordata Miller, termed Common Lime or Tilia x europaea L. In Germany the genus in termed Linden and in eastern North America Basswood. But Linnaeus, probably following the Braintree/Notley resident John Ray, correctly identified it with Tilia of Virgil and Ovid. Presumably the downtown Braintree tree is not old or Native enough for Ray to have studied it himself.
Tilia platyphyllos
Tilia leaf
The example of a test of leaves was started on October 17 with the collection of 10 yellow fallen and 10 picked green Tilia leaves at Braintree (west of the southern end of New Street and fallen on to a parking lot). After five hours in a plastic bag they were floated in all the recently illustrated buckets and tanks of seawater. A brown set collected on January 30 2001 was dried between newspapers before being similarly tested 26 days later.
The sinking of these leaves in buckets and tanks did not appear to depend on water quality. It involved estimation of times when they sink in the night, or between observations. My method has been to stay up for the first and last sinkings of a set, if sinking looked eminent, and not worry too much if the sinkings around the average had to be roughly estimated. Usually I have studied undried leaves so I was not satisfied with the seven previous Tilia times from dried brown and decayed material. The results for the tree sets are as follows (latest at 15°C):
Brown (7) Av. 6.67 days (range 0.847-10.124)
Yellow (10) Av. 2.1165 days (range 0.811-6.679)
Green (10) Av. 2.178 days (range 1.654-2.694)
The average dimensions of the green set were 85.9 mm by 78.5 mm width on the leaf itself, and 126.8 mm inclusive of the peteole or stem. The largest actually sank fist and had corresponding dimension of 128 mm by 123 mm, and 175 mm total length. The yellow set provides a more natural sampling of the leaf fall and averaged 67.0 mm by 61.8 mm width, with a total length of 96.0 mm. The largest leaf was the last to sink, probably because the peteole was shorter than the penultimate sinking of one with the same overall length of 130 to 131 mm in 3.047 days. These two yellow leaves respectively measured 80 by 68 mm width and 93 by 74 mm width on the leaf itself. Where the leaf was longer on the sides than along the central vein I measured the later, and where damage to the tip had occurred I estimated this length. The damaged leaves actually had averaged times and were relatively small, but the two longer floating yellow leaves did look thinner and paler on the upper surface when finally dried-out.
Incidentally, I am not sure which species this downtown Braintree belongs too. Judging from the larger leaf size, it would be Tilia platyphyllos Scopoli; but the hairs on the lower side of the leaf were confined to vein branches as in the hybrid between it and the Nature north Essex Tilia cordata Miller, termed Common Lime or Tilia x europaea L. In Germany the genus in termed Linden and in eastern North America Basswood. But Linnaeus, probably following the Braintree/Notley resident John Ray, correctly identified it with Tilia of Virgil and Ovid. Presumably the downtown Braintree tree is not old or Native enough for Ray to have studied it himself.
Tilia platyphyllos
Thursday, November 02, 2006
Drifted L.E.C.A.
October 14 2006. The Light-weight Expanded Clay Aggregates (L.E.C.A.) found stranded on Chalkwell Beach on October 9 and sampled coming in with the tide at Westcliff the next day correspond to a sentence by G.C. Cadée in his article on Texel beaches in The Drifting Seed vol. 11 no. 2 p.5 (Sept. 2005) namely “building stones of this expanded clay are made and those much larger stones one can find also in drift on our beaches.” His report was mainly about 7 mm spheres found there, with yellowish surfaces around dark purple coloured shallow cracks. both were made by calcination of the middle London Clay Formation at 1200°C in the LECA (G.B.) pits and factory at Mill Lane, High Ongar, Essex c. 1968-1995. However they are potentially made from various clay sites around the world and I have assumed that the Ongar pits ran out of clay, at least from there. On taking both the drifted material and part of one currently being used on a building site to a builders merchant, I was informed that they are marketed as CELLON BLOCKS but not where they are currently made. They doubtless get put into the sea either by illegal flytippers, or as part of official dumping of hardcore to improve sea defenses, and then float away!! I had not noticed them before and initially assumed that Lower Greensand Cretaceous sandstone pebbles in the recently repaired seawall had already come loose. They might also be confused with concrete until picked-up and the following description is made here for beachcombers and geologists.
As seen on building sites the blocks are rectangular with a length around one foot or 30 cm (I am not sure exactly which; doubtless 30cm in the Netherlands) with easily broken edges showing a pitted, rather than actually porous, rough interior. Two colours were seen both on the beach and on house building sites at Southend-on-Sea this week. A dry inland fragment (110 by 85 by 60 mm) was light bluish grey (5B 6/1), changing on both the submerged and the emerged surfaces to dark bluish grey (5B 3/1) after about five hours in an oxygenated seawater tank. The other type is very light grey (N8) and represented by the sample taken from the sea (180 by 130 by 60 mm worn subtriangle) given a light greenish grey (5G 8/1) colour by a thin film of algae and having dark yellowish grey colour (5Y 7/1) on the less easily coated original surface of the block. The latter look very much like clay which has been cut and smeared by a spade or mechanical digger, while the rough surface of both colour varieties consists of rather square 0.5 to 0.8 mm wide pits, between thin walls of silty vitrified clay showing a few dark spots of what was once presumably pyrite. Perhaps the blue variety is a more originally pyritic clay, or more likely one processed in a more reducing environment. One of the yellowish blocks from the beach was placed in the deoxygenated seawater bucket for two days and seen to go uniformly dark bluish grey below the waterline. This stain differs from the hydrogen sulphide staining of the wood, bone and aragonite shells on Chalkwell foreshore in being entirely lost again when exposed to dry air overnight. Both varieties have 10 to 20% of the volume above the waterline and do not appear to be sinking like pumice initially does.
As seen on building sites the blocks are rectangular with a length around one foot or 30 cm (I am not sure exactly which; doubtless 30cm in the Netherlands) with easily broken edges showing a pitted, rather than actually porous, rough interior. Two colours were seen both on the beach and on house building sites at Southend-on-Sea this week. A dry inland fragment (110 by 85 by 60 mm) was light bluish grey (5B 6/1), changing on both the submerged and the emerged surfaces to dark bluish grey (5B 3/1) after about five hours in an oxygenated seawater tank. The other type is very light grey (N8) and represented by the sample taken from the sea (180 by 130 by 60 mm worn subtriangle) given a light greenish grey (5G 8/1) colour by a thin film of algae and having dark yellowish grey colour (5Y 7/1) on the less easily coated original surface of the block. The latter look very much like clay which has been cut and smeared by a spade or mechanical digger, while the rough surface of both colour varieties consists of rather square 0.5 to 0.8 mm wide pits, between thin walls of silty vitrified clay showing a few dark spots of what was once presumably pyrite. Perhaps the blue variety is a more originally pyritic clay, or more likely one processed in a more reducing environment. One of the yellowish blocks from the beach was placed in the deoxygenated seawater bucket for two days and seen to go uniformly dark bluish grey below the waterline. This stain differs from the hydrogen sulphide staining of the wood, bone and aragonite shells on Chalkwell foreshore in being entirely lost again when exposed to dry air overnight. Both varieties have 10 to 20% of the volume above the waterline and do not appear to be sinking like pumice initially does.
Weather records on London Clay subsidence 2006.
October 12 2006. The previously cited qualitative records of rain during this dry year on the London Clay illustrated (September 29 2006) can be compared to rain gauge records in decimal inches made by John Bird in his garden 0.35 km east of the photograph of Eastwood. Combined with my observations of when it rained during the day these diurnal totals can be put in order as a guide to likely flash floods in 2006:
Overnight April 9/10 0.78 (April total 1.54)
Rains until evening October 6 0.6 inch
Evening thunderstorm Sept 13 0.5 (Sept. total 1.04)
Overnight May 6/7 0.48 (May total 3.00)
Overnight Aug. 23/24 0.38 (Aug. tot. 2.10)
Continues daylight Aug. 23 0.38
Afternoon x later March 7 0.30 (March total 1.15)
Around 1hrs. G.M.T. August 17 0.23
Around 4 hrs. G.M.T. August 28 0.22
General “some rain” on June 15 0.22 (June total 0.73)
Rain x windy night Feb. 15 0.22 (Feb total 0.84)
It will be seen that much of the monthly rainfall took place on single days or nights, and often with most of it falling within an hour or so, in sudden bursts on a time-scale of a few minutes. This water then runs off the modern gardens converted into parking lots, decking and sheds, as well as roof areas, which were originally designed to similarly flood the street and sewers, not wet the subsoil. consequently most of the water forms a torrent down the street and a flash flood in the river despite improvements made to stop it overflooding the road seen in the photograph (which used to flood, but not now the river is in a deeper concrete channel). A more sustained gentle rain would have been better for reducing subsidence claims even in tradition gardens.
Looking now at the monthly rainfall totals from the same local source one needs to also consider when the hawthorn and other more substantial local trees developed leaves able to extract water from their tiny roots below dwellings (although the conifers, often more popular in gardens obviously operate all the year). The leaves have recently been falling in November and appear again in the middle of April (my diary notes April 14 2006 for a hawthorn, which I had fully removed because it was causing damage by September 10). It did not help that the first third of the year was also unusually dry (Jan. 0.68, Feb. 0.84, March 1.15), but there was some improvement in the spring (April 1.54, May 3.00) causing a large development of leaves, which partly became yellow and fell-off during the summer drought (June 0.73, July 0.29). Rain did return on August 12/13 but not in substantial amounts until the end of the month when it came in the potential flash floods recorded above (Aug. tot. 2.10, Sept. 1.04). These records are only up to October 11 but the present month is clearly relatively wet and the cracks in buildings are closing up. It is unavoidable that some trees have to be removed due to this type of dry weather and their proximity to dwellings with concrete foundations resting in the London Clay. However removal of all the trees from Essex, now increasingly covered in this way by dwellings and concrete, will contribute to climate change globally and to flash flooding locally.
In the longer-term the sea level and tidal range at Rochford will influence the ability of the river shown on the left of the photograph to discharge any rain which happens to fall when the tide is in. Before the late 18th Century there was no road there and it was termed a mead.
Overnight April 9/10 0.78 (April total 1.54)
Rains until evening October 6 0.6 inch
Evening thunderstorm Sept 13 0.5 (Sept. total 1.04)
Overnight May 6/7 0.48 (May total 3.00)
Overnight Aug. 23/24 0.38 (Aug. tot. 2.10)
Continues daylight Aug. 23 0.38
Afternoon x later March 7 0.30 (March total 1.15)
Around 1hrs. G.M.T. August 17 0.23
Around 4 hrs. G.M.T. August 28 0.22
General “some rain” on June 15 0.22 (June total 0.73)
Rain x windy night Feb. 15 0.22 (Feb total 0.84)
It will be seen that much of the monthly rainfall took place on single days or nights, and often with most of it falling within an hour or so, in sudden bursts on a time-scale of a few minutes. This water then runs off the modern gardens converted into parking lots, decking and sheds, as well as roof areas, which were originally designed to similarly flood the street and sewers, not wet the subsoil. consequently most of the water forms a torrent down the street and a flash flood in the river despite improvements made to stop it overflooding the road seen in the photograph (which used to flood, but not now the river is in a deeper concrete channel). A more sustained gentle rain would have been better for reducing subsidence claims even in tradition gardens.
Looking now at the monthly rainfall totals from the same local source one needs to also consider when the hawthorn and other more substantial local trees developed leaves able to extract water from their tiny roots below dwellings (although the conifers, often more popular in gardens obviously operate all the year). The leaves have recently been falling in November and appear again in the middle of April (my diary notes April 14 2006 for a hawthorn, which I had fully removed because it was causing damage by September 10). It did not help that the first third of the year was also unusually dry (Jan. 0.68, Feb. 0.84, March 1.15), but there was some improvement in the spring (April 1.54, May 3.00) causing a large development of leaves, which partly became yellow and fell-off during the summer drought (June 0.73, July 0.29). Rain did return on August 12/13 but not in substantial amounts until the end of the month when it came in the potential flash floods recorded above (Aug. tot. 2.10, Sept. 1.04). These records are only up to October 11 but the present month is clearly relatively wet and the cracks in buildings are closing up. It is unavoidable that some trees have to be removed due to this type of dry weather and their proximity to dwellings with concrete foundations resting in the London Clay. However removal of all the trees from Essex, now increasingly covered in this way by dwellings and concrete, will contribute to climate change globally and to flash flooding locally.
In the longer-term the sea level and tidal range at Rochford will influence the ability of the river shown on the left of the photograph to discharge any rain which happens to fall when the tide is in. Before the late 18th Century there was no road there and it was termed a mead.
Stranded L.E.C.A. and apples
October 10 2006. The highest predicted tide at Chalkwell, not only this year but for several others, was yesterday afternoon at 3.4 m above mean sea level, and both tides on the 8th and the 13.35 G.M.T. tide today were predicted as 3.3 m. Presumably this is due to the unusual size and yellow appearance of the Harvest moon, which was so impressive at the end of last week. Also a quarter of an inch of rain fell locally on October 5. This resulting flash flood and high tides evidently a gravel ridge, capped with rolls of algae concentrated on the west sides of breakwaters, before the highest predicted tide arrived. This ridge did not look much different this morning. It had just gathered more algae, plus a new element, Sea Purslane leaves removed from upper beaches and marches by high tides. It was more instructive to observe much the same floating materials in today’s high tide before it could amalgamate them with less buoyant and older stranded material on the beach. The material actually seen coming in floating with the tide over a studied distance of 1.7 km were two brown oak leaves, 15 conspicuous feathers (mainly gulls up to 320 mm length, but including two of the banded ?Curlew feathers discussed previously of 225 mm length); large rafts of Sea Purslane leaves (Halimione portula coides (L.), which floated for 48.2 days when picked and tested in December 2000) and sea grass (Zosteras),this became more common towards Westcliff than the Sea Purslane presumably coming from Leigh March rather than intertidal sands); much large human wood debris evidently coming from a flooded café selling cockels, but perhaps not directly and a floating building stone discussed below and a few plastic bottles and drink cans. In addition there were a few floating sticks.
Below this level in the sea was a swash zone of non-buoyant material being suspended by the waves and moved on to the beach above even less buoyant strandline material such as stones and open bivalve shells (Mytilus x Mercenaria). The suspended material included one large and one small dead Common Crab (Carcirus), brown algae and other vegetation bound into rolls along the edge of the incoming tide, one or two brown leaves of genera other than oak, a cone of Pinus nigra and a cultivated apple. Neither of these floated when taken home and tested in more static seawater, although they appeared to do so due to the motion of the waves. Apples but not pine cones were also conspicuous on the gravel ridge made recently, as was the building stone debris. They are therefore reviewed here.
At first sight one assumes the brown and deplorable state of the apple is due to the work of the sea, and seabirds, while it was gradually becoming non-buoyant on the intertidal mudflats. However, both the pitting and brown to black external colouration matches an apple of the same size and shape picked from the wet soil inland today. They even turned brown when kept dry and away from Magpies, after a few days indoors; while these placed directly in seawater look unaltered and can float well (as do the brown previously decayed type). The drifted apple had an equatorial diameter of 55 mm and a height diameter of 42mm, on a short stalk. One side was black and crushed, and corresponded to the bruised zone caused by landing inland. Stranding in the swash before collection produced radial cracks, which lost air when refloated. The only significant differences between the two brown and pecked apples were seen after cutting in half. The stranded one had flesh of the same orange colour, which was firmer and non-buoyant in seawater, and the core lacked seeds. It was not clear why the seeds were missing although insect borings along the stem might have been missed in such a decayed structure. Clearly the stranded apple was a red to yellow variety of Malus domestica Borkhausen which is unlikely to have been sold to the English public in that state and probably came from rejected garden waste, or in a flash flood (they do float in tap water for over a day even when brown and from wet soil). Obviously the many apples seen on Southend beaches earlier in the year have just been rejected from lunch boxes, being out of season and quite undecayed. Tested Crab Apples float much less well and probably cannot reach the sea in rivers at all (see also photographs taken October 7th).
Below this level in the sea was a swash zone of non-buoyant material being suspended by the waves and moved on to the beach above even less buoyant strandline material such as stones and open bivalve shells (Mytilus x Mercenaria). The suspended material included one large and one small dead Common Crab (Carcirus), brown algae and other vegetation bound into rolls along the edge of the incoming tide, one or two brown leaves of genera other than oak, a cone of Pinus nigra and a cultivated apple. Neither of these floated when taken home and tested in more static seawater, although they appeared to do so due to the motion of the waves. Apples but not pine cones were also conspicuous on the gravel ridge made recently, as was the building stone debris. They are therefore reviewed here.
At first sight one assumes the brown and deplorable state of the apple is due to the work of the sea, and seabirds, while it was gradually becoming non-buoyant on the intertidal mudflats. However, both the pitting and brown to black external colouration matches an apple of the same size and shape picked from the wet soil inland today. They even turned brown when kept dry and away from Magpies, after a few days indoors; while these placed directly in seawater look unaltered and can float well (as do the brown previously decayed type). The drifted apple had an equatorial diameter of 55 mm and a height diameter of 42mm, on a short stalk. One side was black and crushed, and corresponded to the bruised zone caused by landing inland. Stranding in the swash before collection produced radial cracks, which lost air when refloated. The only significant differences between the two brown and pecked apples were seen after cutting in half. The stranded one had flesh of the same orange colour, which was firmer and non-buoyant in seawater, and the core lacked seeds. It was not clear why the seeds were missing although insect borings along the stem might have been missed in such a decayed structure. Clearly the stranded apple was a red to yellow variety of Malus domestica Borkhausen which is unlikely to have been sold to the English public in that state and probably came from rejected garden waste, or in a flash flood (they do float in tap water for over a day even when brown and from wet soil). Obviously the many apples seen on Southend beaches earlier in the year have just been rejected from lunch boxes, being out of season and quite undecayed. Tested Crab Apples float much less well and probably cannot reach the sea in rivers at all (see also photographs taken October 7th).
Coconuts and Pinecones
October 8 2006.
coconuts and pinecones
A second pair of photographs taken yesterday shows dried pinecones and coconuts at slightly different angles and illuminations. The bowl shows Pinus nigra cones dried-out after having sunk recently. The greater size of the now fully dry pinecone stranded at Chalkwell on April 7 2006 is illustrated by placing it beside them on the bottom left hand side of the four coconuts. Probably it is Pinus pinaster Aiton, with the apical scales fibrous and partly missing by the combined effects of maturation on the tree and beach erosion, prior to the final episode of marine transport from an unknown (English?) beach. Two of the coconuts also stranded in the Southend-on-Sea area, probably after being released into London canals for Hindu Rituals. The one on the top left stranded at Thorpe Bay during a S.W. gale at 16 hours. G.M.T. on January 13 2004, and shows a triangular mass of coir fibres truncated into a 10 mm diameter facet by Man rather than a natural erosive process in the Gulf Stream. It was then floated in the illustrated bucket, without drying during collection or major weight gains until it was removed on July 12 2006. During this time in the bucket the mass decreased from a maximum of about 806 g to about 673 g, and the orientation changed from coir-apex down to horizontal, presumably because the endosperm white flesh of the coconut gradually decayed. Certainly it now rattles about in this new even less dense dry state. One of the eyes was open enough for air bubbles to exit it when collected. An old water line in the bucket experiment can be hopefully seen on the photograph defined by a white band with a chord diameter of 80 mm on the opposite end of the nut from the coir fibres around the eyes. The overall length is 170 mm and the equatorial diameter 110 mm.
The stranded coconut on the top right is the one discussed on this blog and was found near Chalkwell Shelter on April 2 2006, with the husk separated and one of the eyes which had been covered by it seen to have a tunnel of white endosperm below it. In this case the husk looks more extensive than that seen usually on sale in England.; but might presumably have been imported for a Hindu niche market. I wish I knew exactly how Hindu’s prepare their coconuts for ritual refloatations and when. The usually cited and observed canal and coastal rituals are roughly in August and not when I see strandings at Southend. Natural drifting with the Gulf Stream is possible but would seem likely to produce more evidence of marine encrustation. Illustrations of stranded coconuts at intermediate sites would be instructive if they show what form the husk has after being floated by hurricanes etc.
The two lower coconuts were purchased from an English supermarket, where they are sold with less husk present than in some Green grocers shops. They are coconuts A (left) and B (right) of my notes in The Drifted Seed 2005 and 2006. The photograph is mainly of interest in showing that coconut B has become black during a second summer of drying after having sunk in seawater. The other coconut A shows the colouration after drying for just one summer and when any coconut has been in seawater for a day or so it is dark brown. In terms of mass changes in coconut B, there was an increase from about 550 g when purchases., to 620 g just after it sank and 644 g when drying started on day 626 of the experiment. Dehydration and perhaps some decay reduced the mass to 339 g on day 802; but after the nut became black again and leaked green copra oil from the eye the mass was further reduced to 259 g on day 1100 (which was just prior to the photography). Curiously when half-coconuts are left exposed to the air and not eaten by birds the flesh seems relatively stable at English temperatures.
coconuts and pinecones
A second pair of photographs taken yesterday shows dried pinecones and coconuts at slightly different angles and illuminations. The bowl shows Pinus nigra cones dried-out after having sunk recently. The greater size of the now fully dry pinecone stranded at Chalkwell on April 7 2006 is illustrated by placing it beside them on the bottom left hand side of the four coconuts. Probably it is Pinus pinaster Aiton, with the apical scales fibrous and partly missing by the combined effects of maturation on the tree and beach erosion, prior to the final episode of marine transport from an unknown (English?) beach. Two of the coconuts also stranded in the Southend-on-Sea area, probably after being released into London canals for Hindu Rituals. The one on the top left stranded at Thorpe Bay during a S.W. gale at 16 hours. G.M.T. on January 13 2004, and shows a triangular mass of coir fibres truncated into a 10 mm diameter facet by Man rather than a natural erosive process in the Gulf Stream. It was then floated in the illustrated bucket, without drying during collection or major weight gains until it was removed on July 12 2006. During this time in the bucket the mass decreased from a maximum of about 806 g to about 673 g, and the orientation changed from coir-apex down to horizontal, presumably because the endosperm white flesh of the coconut gradually decayed. Certainly it now rattles about in this new even less dense dry state. One of the eyes was open enough for air bubbles to exit it when collected. An old water line in the bucket experiment can be hopefully seen on the photograph defined by a white band with a chord diameter of 80 mm on the opposite end of the nut from the coir fibres around the eyes. The overall length is 170 mm and the equatorial diameter 110 mm.
The stranded coconut on the top right is the one discussed on this blog and was found near Chalkwell Shelter on April 2 2006, with the husk separated and one of the eyes which had been covered by it seen to have a tunnel of white endosperm below it. In this case the husk looks more extensive than that seen usually on sale in England.; but might presumably have been imported for a Hindu niche market. I wish I knew exactly how Hindu’s prepare their coconuts for ritual refloatations and when. The usually cited and observed canal and coastal rituals are roughly in August and not when I see strandings at Southend. Natural drifting with the Gulf Stream is possible but would seem likely to produce more evidence of marine encrustation. Illustrations of stranded coconuts at intermediate sites would be instructive if they show what form the husk has after being floated by hurricanes etc.
The two lower coconuts were purchased from an English supermarket, where they are sold with less husk present than in some Green grocers shops. They are coconuts A (left) and B (right) of my notes in The Drifted Seed 2005 and 2006. The photograph is mainly of interest in showing that coconut B has become black during a second summer of drying after having sunk in seawater. The other coconut A shows the colouration after drying for just one summer and when any coconut has been in seawater for a day or so it is dark brown. In terms of mass changes in coconut B, there was an increase from about 550 g when purchases., to 620 g just after it sank and 644 g when drying started on day 626 of the experiment. Dehydration and perhaps some decay reduced the mass to 339 g on day 802; but after the nut became black again and leaked green copra oil from the eye the mass was further reduced to 259 g on day 1100 (which was just prior to the photography). Curiously when half-coconuts are left exposed to the air and not eaten by birds the flesh seems relatively stable at English temperatures.
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