[ 457 ] 



LIX. Notices respecting New Booh. 



The Strength of Materials and Strictures. By John Andeeson, 



C.E., LL.D., F.R.S.E., <${c. London : Longmans, Green, and Co. 



1872 (pp. 301). 

 rpHIS book consists of two parts, the first treating of "the 

 -*- strength of materials, as depending on their quality, and as 

 ascertained by testing-apparatus," the second treating of " the 

 strength of structures, as depending on the form and arrangement 

 of their parts, and on the materials of which they are constructed." 

 In the first part, after a few preliminary remarks, the author gives 

 an account of the machine in use at Woolwich for testing the 

 strength of materials, particularly when exposed to tensile or com- 

 pressive stresses. He then passes in review the principal materials 

 used in constructions, with especial reference to their behaviour in 

 the testing-machine ; he devotes a chapter apiece to cast iron, 

 wrought iron, and steel, one to copper aud other metals and their 

 alloys, one to timber, and finally gives, somewhat briefly, notices 

 of the resistances offered by materials to impact, torsion, and 

 shearing. The results obtained by experiment are gone into with a 

 good deal of minuteness, and are also recorded in Tables, which, 

 in the first part, are as many as thirty-eight in number. Many of 

 these Tables give results which have, to all appearance, been ob- 

 tained under the author's superintendence ; others are taken from 

 writings of authority, e. g. from the Eeport of the Commissioners 

 appointed to inquire into the Application of Iron to Eailway 

 Structures. 



This part of the work contains a great deal of valuable informa- 

 tion, and will repay attentive study by any one interested in me- 

 chanical science, whether a workman or not. A critical reader 

 might notice here and there a trace of want of practice in literary 

 composition; this, however, is a trifling defect, and in nowise 

 diminishes the solid value of a book written by one who has had a 

 long and intimate acquaintance with his subject. 



The second part is of a somewhat miscellaneous character ; it is 

 devoted to questions regarding the strength of girders, trusses, 

 boilers, &c. Its chief interest consists in the fact that the struc- 

 tures which come under discussion have been actually erected by 

 the author. The reader is therefore enabled to see how the proper 

 mechanical rules are employed in designing actual works. To our 

 mind, the best example given in this part of the work is that of the 

 30-ton crane, which forms a most instructive mechanical " study." 



There is a tendency observable throughout the book to treat the 

 subject as if it consisted of isolated points ; even where points are 

 closely connected, the fact of the connexion is sometimes ignored. 

 A good instance of this is the manner in which the author treats 

 the subject of deflection. He lays down several rules appli- 

 cable to the subject — for instance, that a rectangular beam, sup- 

 ported at both ends and loaded at the centre, has a deflection in 



