In a message dated 13/12/97 04:44:00 GMT, Vergil Noble wrote
 
<< The ball is precisely 15 pounds in weight with a circumference of
      about 15 1/2 or 15 5/8 inches (approx. 5 inches in diameter).  Anyone
      know if this can be dated and, if so, when would it have likely seen
      use?.  Please feel free to provide either a recollection or citation.
  >>
5 ins shot should be over 17lb and 4.75 ins shot very slightly under 15lb.
 This is the size of shot used in ordinary/small English "culverins" of 5 1/4
ins or 5 ins calibre respectively in the late 16th to the mid 18th century. A
small culverin seems most likely going by the weight. By the 1750s six inch
and four/three inch calibre guns seem to be the English norm. See H. L.
Blackmore, _The Armouries of the Tower of London: The Ordnance_, 1976 (out of
print). However, French and American ordnance may have different standards.
Paul Courtney, leicester, UK