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A patron asked me the meaning of a symbol on a provisional edition
of a topo sheet, and I didn't recognize it.  It looks like
"crosshairs," i.e., a circle divided in four, and it occurs in
various places on the map.  Next to each one is a hyphenated group of
numerals, such as 1-112, 2-27, etc.  My guess is that it has to do
with the sequence of aerial photos used for surveying the area, and
that they'll gone if the sheet is published in its final form.  Is
this correct?                  -- KR
 
 
 
Ken Rockwell
"Just another map librarian" at
Marriott Library
University of Utah
Salt Lake City, Utah
 
"Without Geography--you're NOWHERE!"