[Cob] Jar Method?

[Amanda Peck]

Silt, clay, sand all settle out at different rates.  So if you put some of 
your sample in a jar, add water, leaving room to shake it up good, then let 
it set for a day, you should have pretty well defined layers, with the clay 
on top.  I have lots of silt down at the bottom of the hill, so I've had to 
work what I thought was clay to make sure it really was.   Silt has very few 
desirable building properties.

Here are the instructions from Becky Bee's book.

http://www.weblife.org/cob/cob_043.html
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Beno asks:
I just came across a post in the archives about the "jar method" for 
determining clay content in soil. What is this? How does it work?