Sunday, September 30, 2012

Artifacts of the Seven Site: The Southeast Ferrous Feature



Southeast  Ferrous Feature: General Description

The Southeast Ferrous Feature at the Seven Site is a more or less linear concentration of highly oxidized ferrous fragments and rust just southeast of the 2010 “L” lanes and northwest of the 2010 “X” area (Figure 1). 
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The feature trends roughly S-SW down the slope of the ridge, covering a linear distance of about seven meters.  We documented it photographically, with video, and with a sketch-plan on June 4, 2010, and took samples of larger and relatively identifiable fragments from six locations, shown in Figure 2.  Figure 3 shows the feature as viewed from the photo tower at an elevation of about 3 meters.
   
 
 
Figure 2: Plan of SE Ferrous Feature


 Figure 3:  Upper (NE) part of feature from photo tower
 


Samples were simply collections of the larger and more likely-to-be-identifiable fragments from selected locations along the length of the feature, most of which consisted of ferrous but otherwise unidentifiable fragments and plain rust.  Each sample was bagged, labeled, catalogued and brought back to the U.S. for analysis.  Analysis consisted of close examination under magnification as necessary, and classification into types based on gross morphology.

General Characterization of the Feature

Although very badly deteriorated, the organization of fragment concentrations on the ground resembled a collection of more-or-less similar-sized rectangular corrugated iron sheets.  It appeared that there were at least five sheets, approximating the dimensions of corrugated sheets measured in the village at Ritiati (each 70x275 cm.).  Precise measurements could not be obtained on the components of the SE ferrous feature due to the deteriorated and scattered condition of the deposits.  Some sheets appeared to be stacked or overlapping, and some fragments were thick enough to represent two or three stacked sheets. 

Characterization of Sample 1 (Cat. # 2-9-S-83A)

Sample 1 (Catalogue # 2-9-S-83A) came from near the northeast end of the feature.  Besides small indeterminate fragments, it included the following:

Four fragments of flat ferrous metal, rectangular to subrectangular, each with at least one straight, apparently machined, edge

·         Dimensions: 65.9x26.94x4.16 mm; Description:  1 edge machined, the other broken, very slight “lip.”
·         Dimensions:  47.67x24.13x4.39 mm; Description: 1 edge probably machined, other broken, very slight “lip” curved at roughly right angle to the cross-section.
·         Dimensions: 34.74x21.62x4.06 mm; Description:  Laminated.  1 edge probably machined, other broken
·         Dimensions: 42.84x25.79x4.38 mm. Description:  Laminated.  1 edge probably machined, other broken, distinct bend.

Five fragments probable corrugated iron – amorphous in shape, laminated, curved.

·         Largest: 42.61x28.6x3.94 mm.
·         Smallest  23.62x22.8x3.46; something of a straight edge and lip

Comments:  The corrugated iron appears consistent with corrugated siding/roofing.  The rectangular/subrectangular fragments are notable by being of rather consistent width – 22 to 27 mm. – and having one long edge that seems to have broken along a right-angle bend parallel to the long axis of the object.

Characterization of Sample 2 (Cat. # 2-9-S-83B)

Sample 2 came from just upslope of the feature’s midpoint, in an area where it looked like two or more sheets might have overlapped.  In addition to unidentifiable fragments, Sample 2 contained:

Five evident pieces of heavy and/or multi-layer corrugated –curved cross-section, sub-rectangular to amorphous in shape: 

·         Dimensions:  61.66x36.81x5.3 mm.
·         Dimensions:  43.18x36.28x4.16 mm.
·         Dimensions:  29.92x35.82x3.95 mm.
·         Dimensions:  45.4x26.57x4.1 mm.
·         Dimensions:  34.54x32.14x4.02 mm.

Six rectangular to subrectangular flat fragments with parallel long edges

·         Dimensions:  52.32x24.19x4.77mm; Description:  One edge machined, other broken but relatively straight
·         Dimensions: 35.77x21.34x3.64 mm; Description:  One edge possibly machined, other slightly bent, broken
·         Dimensions: 32.88x23.4x4.46 mm; Description: Laminated, one edge possibly  machined, other broken but straight
·         Dimensions:  27.83x23.52x4.68 mm; Description:  One edge machined, other broken
·         Dimensions:  28.39x21.57x3.62 mm; Description:  Both parallel edges machined?
·         Dimensions:  35.87x21.03x4.23  mm; Description: Laminated, straight edge is bent and broken; other edge irregular

Two flat fragments, subrectangular but no evident finished edges

·         Dimensions:  47.74x17.12x5.36 mm.
·         Dimensions:  46.48x17.35x5.04 mm.

About 20 smaller, amorphous fragments, thickness equivalent to above

Comments:  As in Sample 1, there appear to be two kinds of ferrous object here: corrugated iron siding/roofing and flat pieces of consistent thickness and width, some with one long edge exhibiting a bend parallel to the long axis of the object.


Characterization of Sample 3 (Cat. # 2-9-S-83C)

Sample 3 was southeast of Sample 2, at another location where it appeared that two sheets overlapped – one running NE-SW, the other NW-SE.  Sample 3 included some 15 non-diagnostic fragments, flakes, and rust-dust, together with:

12 fragments of various sizes, apparent thick or stacked corrugated – characterized by curved cross-sections and generally amorphous shapes though with some straight edges that appeared to represent breaks along the peak or trough of corrugations.  .

·         Largest, dimensions:  46.88x35.1x4.87 mm.; Description: one straight edge, looks broken
·         Mid-range, dimensions:  37.06x34.97x4.78 mm.;  Description: amorphous.
·         Smallest, dimensions:  22.43x23.07x4.46 mm.; Description:  Laminated, looks like it represents multiple (2? 3?) sheets.

Four  Subrectangular straight sided

·         Dimensions:  77.8x28.4x3.48 mm.; Description:  Laminated.  one edge machined; opposite edge has pronounced bend
·         Dimensions:  57.10x23.8x4.81 mm.;  Description:  Both parallel sides broken; one has something of a lip/bend
·         Dimensions:  44.46x15.86x4.23 mm.; Description:  One edge appears machined, the other has a pronounced bend – strange because this one is narrower than others with this trait.
·         Dimensions:  53.82x37.97x4.7 mm.; Description:  Laminated; one edge appears broken, not machined; opposite has pronounced lip or bend.  Strange because WIDER than others with this trait.

Ca. 15 small amorphous fragments equivalent in thicknesses to the above

Comments:  Here again there appear to be two essential kinds of ferrous material: corrugated iron and something resembling a metal bar with an L-shaped cross-section, which has consistently failed along the bend between the “L’s” two legs.  Each leg of the “L” – that is, each side of the L-shaped bar – here as in the other samples, seems to have been between 22 and 28 mm wide.  Oddities in this sample only are one piece that appears to retain the bend between the two legs of the L, but is almost 40 mm. wide, and another that appears to retain the bend and an opposing finished edge but is less than 16 mm. wide.

Characterization of Sample 4 (Cat. # 2-9-S-83D)

Sample 4 was at the far SW end of the feature.  It contained:

Twenty-one mostly large, heavy pieces, slightly to obviously curved in cross-section, fairly irregular to subrectangular in shape, often clearly laminated.  These appear to represent multiple stacked sheets of corrugated iron.

Examples:

·         Largest:  56.49x75.27x5.08 mm.
·         Smallest:  21.03x24.55x3.24 mm.

Unusual and interesting: 

·         Dimensions:  39.05x37.06x5.47 mm.  Description:  Lazy S cross section not inconsistent with corrugated but probably from near edge of sheet.

Six flat, subrectangular fragments fairly consistent in width, not laminated. 

Examples:

·         Largest:  Dimensions:  40.49x23.47x4.07 mm.
·         Smallest:  Dimensions:  33.46x19.93x3.88 ,,/

Comments:  Consistent with the other samples, Sample 4 appears to consist of corrugated iron fragments and fragments of a bar, whose dimensions are consistent with those of the apparent L-cross-section bar found in other samples, but without evidence of the bend connecting the two legs of the L.

Characterization of Sample 5 (Cat. # 2-9-S-83E)

Sample 5 was from the southernmost edge of the feature, at what appeared to be the end of a sheet of corrugated metal with its long axis running NE-SW.  It contained some thirty ferrous fragments, the largest fifteen of which are described below:

One probable fragment of corrugated iron

·         Dimensions:  38.86x21.97x5.85 mm.; Description: amorphous, curved cross-section, heavily laminated

Rectangular to subrectangular fragments:

·         Dimensions:  46.9x26.27x4.6 mm.; Description:  two parallel edges, one with lip suggesting breakage along a bend
·         Dimensions:  38.42x23.69x3.9 mm.; Description: subrectangular, one long edge machined?
·         Dimensions:  51.33x16.67x4.42 mm.; Description:  one long edge straight, machined?
·         Dimensions:  36.44x20.92x3.9 mm.; Description:  one edge straight, possibly machined.
·         Dimensions:  33.84x18.57x5.07 mm.; Description: subrectangular, both edges broken
·         Dimensions:  24.03x23.89x5.4 mm.; Description: one straight edge, opposite broken.
·         Dimensions:  30.84x20.6x4.35 mm.; Description: subrectangular
·         Dimensions:  41.46x17.59x3.29 mm.; Description: one straight (machined?) edge
·         Dimensions:  32.23x14.91x3.15 mm.; Description: one straight edge

Unusual fragments

·         Dimensions:  27.44x24x4.23 mm.; Description: one straight edge.  Possible pin or rivet opposite but no penetration evident.
·         Dimensions:  44.42x21.24x3.98 mm.; Description:  subrectangular, two parallel straight edges.  One edge appears to be “lined” with square-cross-section wire
·         Dimensions:  25.49x21.01x6.44 mm.;  Description:  subrectangular, heavily laminated, two rather unambiguous pin heads
·         Dimensions:  42.3x25.54x5.99 mm.;  Description:  subrectangular, heavily laminated, cluster of six apparent  pinheads on one side, two on the other
·         Dimensions:  24.51x17.29x3.17 mm.; Description:  subrectangular-amorphous, contains punched hole 2.56 mm diam.
           
Comments:  This sample is generally consistent with the others, being made up of corrugated iron together with what could be an L-cross-section bar with each side being about 3 cm wide, broken along the bend.  The small subrectangular piece with the punched hole could well be a piece of corrugated iron.  The oddities are the pieces with what appear to be pinheads, in one case at least six on one side, two on the other, and the piece with the rectangular cross-section wire along its edge.  Both kinds of object are similar to items found in the SL fire feature, about four to five meters to the north.

Characterization of Sample 6 (Cat. # 2-9-S-83F)

Sample 6 is from near the SW end of the same deposit as Sample 5.  Its contents are summarized below:

Amorphous, no straight edges

·         Dimensions:  45.05x37.09x4.48 mm.; Description: curve consistent with corrugated, laminated
·         Dimensions:  34.87x28.07x2.57 mm.;  Description: curve consistent with corrugated
·         Dimensions:  34.31x32,06x3.96 mm.; Description: curve consistent with corrugated

Flat pieces with straight parallel long sides, one edge of on each often exhibiting a near right-angle bend. 

·         Dimensions: 74.49x33.26x3.05 mm; right-angle bend remnant 7.71 mm. wide; Description:  rectangular.
·         Dimensions: 73.58x22.30x2.71 mm;right-angle bend remnant 10.98 mm wide; Description:  rectangular.
·         Dimensions: 48.49x31.46x4.27 mm; bend remnant 10.02 mm. high; Description:  Angled piece extends out from main body at about 30 degrees.  Edge opposite this bend is parallel to it, perfectly straight, appears machined.
·         Dimensions:  39.1x24.03x3.06 mm; bend remnant 9.07 mm high.  Description: edge is clearly bent over, not two separate welded pieces.
·         Dimensions:  65.41x21.44x4.79 mm.; Description: subrectangular.
·         Dimensions:  51.34x22.77x4.44 mm;  Description; one long edge slightly lipped as though part of bend
·         Dimensions:  35.71x24.22x4.33 mm; Description: clearly laminated
·         Dimensions:  41.44x26.7x4.74 mm; Description:  clearly laminated
·         Dimensions:  38.11x23.53x4.58 mm; Description: very slight curve
·         Dimensions:  42.87x20.14x4.25 mm.; Description: subrectangular
·         Dimensions:  38.60x24.0x4.68 mm; Description:  clearly laminated, more broken of two edges edge curved as though beginning of bend
·         Dimensions:  40.09x27.03x3.46 mm; Description:  one edge slightly lipped as though beginning of bend
·         Dimensions:  41.74x28.39x4.01 mm; Description: one edge very straight, machined.  Opposite lipped like beginning of bend
·         Dimensions:  55.40x26.21x2.91; Description: One very straight machined edge; other edge broken but retains remnant lip

13 other smaller fragments with remnant straight edges, ca. 30 small irregular frags, much rust

Comments:  This sample clearly breaks down into the now-familiar two groups: corrugated iron and bar with L-shaped cross-section, each piece of the bar being about 3 cm wide. 

General, Tentative Conclusions

It appears pretty clear that the SE Ferrous Feature represents a number of corrugated iron sheets, perhaps piled up on the ground, perhaps merely overlapping one another where they fell, together with some iron or steel rods with L-shaped cross-sections.  Such rods are apparently commonly used in fencing, especially in Europe, where they are called “L-Posts” (See http://www.fencepost.net.cn/fence-post/t-l-post-pipepost.html).  The cross-sectional dimensions given for “Euro L-Posts” on the website referenced above are 25x12x4 mm; it is not unreasonable to suppose that somewhat heavier posts are or were manufactured that would have been more consistent with the dimensions of our fragments, but I have not yet undertaken a detailed search for such posts.

If the parallel-sided flat fragments represent “L-Posts,” they may have supported a sort of wall of corrugated iron running down the slope of the Seven Site surge ridge – or been intended for use in some such construction scheme that never reached fruition.  Why anyone would want to build such a wall is a mystery; one can imagine someone attempting a crab-exclusion device, but a wall across the Seven Site seems even less likely to succeed at excluding crabs than was Hadrian’s Wall at excluding Picts and Scots, the Great Wall of China at excluding Mongols, or the Maginot Line at excluding Germans.  Small anti-crab walls around young coconut palms might work; long walls around large areas (assuming the feature was part of such a plan) seem like they would be exercises in futility.  Of course, such considerations didn’t stop the Romans, Chinese, or French from constructing their barriers.

The Solomon Islands team made a point of trying to determine whether their interviewees knew anything about corrugated iron at the Seven Site, and no one evinced any such knowledge[1].  This suggests that the structure or collection of material represented by the SE Ferrous Feature either was not put in place until after the colonists left in 1963, or was put in place well before those alive today frequented the site.  It does not seem plausible that it was a 1944-46 U.S. Coast Guard construction, which surely would have been apparent to colonists using the site in the 1950s.  

The material appears to be too deteriorated to be consistent with a post-1963 date, and we have no record of anything happening on the island after the colonists left that would have produced such a structure.

One possibility is that the ferrous material was brought to the site in about 1940 at Gallagher’s behest, to be used in connection with planting the area in coconuts.  This might be far enough in the past for the former colonists alive today in the Solomons to have no memory of it, though it seems strange that they would not recall seeing the corrugated sheets lying around.

Another possibility is that the SE Ferrous Feature and the other corrugated iron on the site was put there in the 1890s as part of John Arundel’s effort to plant the island, but we have no evidence that Arundel tried to develop the southeast part of the island.

The fragments with what appear to be rectangular cross-section wires and pins in Sample 5 – which are nearly identical to material found in the SL Feature, could mean several different things:

  • That the SL feature is contemporaneous and associated with the SE Ferrous Feature;
  • That whoever used the SL feature salvaged material from the SE Ferrous Feature for use in his or her camp;
  • That the SE Ferrous Feature post-dates the SL feature, and that parts of the former were laid down on top of the latter; or
  • That the SL feature post-dates the SE Ferrous Feature, and something from the former was laid down on top the latter.



[1] Based on the team’s initial reports; it is possible that something will emerge from detailed study of the recordings.