Tunneling: A Practical Treatise., by Charles
   Prelini                     60043
     [Link: http://www.gutenberg.org/6/0/0/4/60043 ]
     [Files: 60043-0.txt; 60043-h.htm]
   Thanks to deaurider, Harry Lamé and the Online Distributed
   Proofreading Team at http://www.pgdp.net (This file was
   produced from images generously made available by The
   Internet Archive)
   Chuck