376 Notices of Books. [July, 



are described. To this is added a table of the names of materials 

 in a great variety of languages. The work seems to have 

 been thoroughly done, and the information is up to the present 

 day, whilst the style is readable and agreeable. We congratulate 

 Dr. Yeats on having produced a book really useful for educational 

 purposes, — adapted, too, for consultation when the work of life has 

 begun, and also suited for more general reading. We are happy 

 to see that the same author intends to carry on the work thus 

 begun by an Industrial and Political History, and by a Technical 

 History of Commerce, and thus to complete a series of works 

 which will enable the young man engaged in commercial 

 pursuits to connect his daily life with the literature which may 

 really enlarge and inform his mind. Men thus trained would do 

 much to wipe away the stigma so often cast at them by foreigners, 

 that the British commercial man exists for the sole purpose of 

 money getting without any higher or intellectual life. 



Electrical Tables and Formula. By Latimer Clark and Robert 

 Sabine. E. and F. N. Spon. 



The paucity of English telegraph literature gives rise to the 

 greatest anticipation when any new work is announced, and 

 when proceeding from the pens of two so well-known electricians 

 and authors as Mr. Latimer Clark and Mr. Robert Sabine many 

 a hope is expressed that it may be found adequate to the wants 

 of the telegraph engineer. The existing literature would seem 

 to be composed of two classes — works requiring a more than 

 ordinary knowledge of elementary mathematics to render their 

 application useful, and those in which the mere principles of 

 the science are stated. The book under consideration is of the 

 former class, though much useful information unembarassed by 

 mathemetical formulae will be met with in the sections devoted 

 to the Laws of Magnetism, Electro-Magnetism, and Induction. 

 It will be more in demand in the office of the chief-engineer than 

 of use to the essentially practical operator. Exception must be 

 made to the employment of the cube knot as a fundamental unit 

 of resistance. A knot is a term occurring in but one branch of 

 telegraphy, and even then the assumption prevents the verifi- 

 cation of the formulae by an individual inquirer. On the other 

 hand, the insertion of the formula 



E! + E 2 + E 3 + ..... +E„ 

 l -G+r I +r 2 +r 3 + W 



as determining the current from a battery of n elements of 

 differing electromotive forces and resistances connected in series, 

 goes far to show that the authors have not been bound down by 

 any erroneous ideas, however conventional. The joining-up of 

 such a series would be considered by some rule-of-thumb operators 



