Hello all,
        We have found a small (approximately 4.5 x 5 cm) piece of slate
associated with the loopholed outer wall of the U.S. Arsenal at Augusta
(constructed 1827-28) which has been ruled with straight lines in both
directions (up and down as well as cross-wise) apparently using some
type of pointed metal instrument.  On the fragment there are some
numbers inscribed in a couple of the cells.  A couple of others cells in
this matrix appear to be empty.
 
        My questions are these: is it possible that this was some sort of
"construction document" (perhaps like a table of offsets or something
similar) rendered permanent by being inscribed on the slate?  We find
lots of roofing slate fragments here, but of thousands of pieces we've
handled, this is the only one which has numbers and lines on it.  Has
anyone run into anything similar?  Is there some other function which
this may have served which I can't think of?  Of course slates were
routinely used to write on but this is a permanent inscription rather
than temporary.  Any suggestions or thoughts on this would be
appreciated, either on or off list.
 
        Thanks in advance for any help in this identification.
 
        Christopher Murphy, Ph.D.
        Department of History and Anthropology
        Augusta State University