654 BELL SYSTEM TECHNICAL JOURNAL 



be described as an elementary treatise, and although hardly of popular 

 nature it will be intelligible to anyone who has had a fairly thorough 

 college course in physics. 



Published by D. Van Nostrand & Co. ($6.00). 



Electric Circuit Theory and the Operational Calculus. John R. Car- 

 son. This book is based upon a course of fifteen lectures delivered 

 recently at the Moore School of Electrical Engineering of the Univer- 

 sity of Pennsylvania. 



The name of Oliver Heaviside is known to engineers the world over. 

 His Operational Calculus, however, is known to and employed by only 

 a relatively few specialists and this, notwithstanding its remarkable 

 properties and wide applicability not only to electric circuit theory 

 but also to the differential equations of mathematical physics. The 

 present author ventures the suggestion that this neglect is due less to 

 the intrinsic difficulties of the subject than to unfortunate obscurities 

 in Heaviside's own exposition. In the present work, the Operational 

 Calculus is made to depend on an integral equation from which the 

 Heaviside rules and formulas are simply but rigorously deducible. It 

 is his hope that this method of approach and exposition will secure a 

 wider use of the Operational Calculus by engineers and physicists and 

 a fuller and more just appreciation of its unique advantages. 



The second part of the volume deals with advanced problems of 

 electric circuit theory and in particular with the theory of the propa- 

 gation of current and voltage in electrical transmission systems. It is 

 hoped that this part will be of interest to electrical engineers generally 

 because, while only a few of the results are original with the present 

 work, most of the transmission theory dealt with is to be found only 

 in scattered memoirs and there accompanied by formidable mathe- 

 matical difificulties. While the method of solution employed in the 

 second part is largely that of the Operational Calculus, the author has 

 not hesitated to employ developments and explanations not to be 

 found in Heaviside. For example, the formulation of the problem as 

 a Poisson integral equation is an original development which has 

 proved quite useful in the numerical solution of complicated problems. 

 The Slime may be said of the chapter on Variable Electric Circuit 

 Theory. 



In view of its two-fold aspect, this work may therefore be regarded 

 either as an exposition and development of the operational calculus 

 with applications to electric circuit theory or as a contribution to ad- 

 vanced electric circuit theory depending upon whether the reader's 

 viewpoint is that of the mathematician or the engineer. 



