JM Hodgson on the MoLAS (Museum of London Archaeological Services) soil
descriptions flow chart (included in/on here as a bitmap file; this may or may
not be copyrighted, so please respect and obey all laws etc.; if you have
trouble reading the file, let me know what format you might want/need, and
i'll try to send another copy):
 
        I am at a loss to recommend what you should, do. The MoLAS scheme is new
to me and it seems illogical and poorly conceived. in several respects. For
example, it first invites the user to rub moist sediment through the fingers.
Later on the top line it asks 'Will the sediment break easily and clearly'.
Moist material sufficiently wetted to roll into a ball (bottom item, second
column) would never break easily and. clearly, nor would it be hard to break
(top of column three). What exactly is the moist state that they start with'?
 
        How too can you form a ball into a U-shape'? They must mean a ribbon as
in other similar schemes. In such schemes too, a silky feel excludes a sticky
one. The MoLAS scheme must give very inconsistent, results. It must mislead. Who
 
devised it.
 
        ADAS have a similar scheme based on hand texturing which is much better
thought out. The USDA used to give similar guidelines to their textural triangle
 
which seem to work. You could. look at them. There is, however, in my opinion no
 
substitute for comparison with samples of known particle-size distribution as in
 
the Soil Survey Handbook.
 
        I hope this is of some help. I would have thought that archaeologists
had by now cracked this one. Disappointing.
 
lazy bastard finally set up a website:
http://home.t-online.de/home/gcarver/
geoff carver
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