Electrical tables and formul :  for use of telegraph inspectors and operators / 
compiled by Latimer Clark and Robert Sabine 
 - London :  E. and F. N. Spon,  1871 
 - vii, 285, [1] p. ;  19 cm. 
<br/><br/> Includes index 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Telegraph--Tables
<br/><br/><label>Dewey Class. No.: </label>621.382