Cathedral, forge, and waterwheel   :  technology and invention in the Middle Ages  print 

 - nyu  HarperCollins Publishers  c1994 
 - 357 p. : ill.    22 cm.  357 p. : ill. ; 22 cm. 
<br/><br/> Frances & Joseph Gies. 
<br/><br/><label>ISBN: </label>0060165901 (cloth) :