MATHEMATICS. 



with philosophical accuracy, only in its connection with iron and 

 steel, and in the influence excited by the earth as a whole, the 

 accurate portions of this work are confined to the investigations con- 

 nected with these metals and the earth. 7'he latter part of the 

 work, however, treats in a more general way of the laws of the 

 connection between Magnetism on the one hand and Galvanism 

 and Thermo- Electricity on the other. The work is divided into 

 Twelve Sections, and each section into numbered articles, each 

 of which states concisely and clearly the subject of the following 

 paragraphs. 



Ball (R. S., A.M.) — EXPERIMENTAL MECHANICS. A 

 Course of Lectures delivered at tbe Royal College of Science for 

 Ireland. By Robert Stawell Ball, A.M., Professor of Applied 

 Mathematics and Mechanics in the Royal College of Science for 

 Ireland (Science and Art Dep?.rtment). Royal 8vo. ids. 



The authot's aim in these twenty Lectures has been to create in the 

 mind of the student physical ideas corresponding to theoretical laws, 

 and thus to produce a work which may be regarded either af a sup- 

 plement or an introduction to manuals of theoretic mechanics. To 

 realize this design, the copious use of experimental illustrations was 

 necessary. The apparatus used in the Lectures and figured in the 

 volume has been principally built up from Professor Willis's most 

 admirable system. In the selection of the subjects, the question of 

 practical utility has in many cases been regarded as the one of para- 

 mount importance, and it is believed that the mode of treatment 

 which is adopted is more or less original. This is especially 

 the case in the Lectures relating to friction, to the mechafiical 

 powers, to the strength of timber and structures, to the laws of 

 motion, and to the pendulum. The illustrations, drawn from 

 the apparatus, are nearly all original and are beautifully exe- 

 cuted. "In our reading we have not met with any book of the sort 

 in English." — Mechanics' Magazine. 



Bayma. — TI-IE ELEMENTS OF MOLECULAR MECHA- 

 NICS. By Joseph Bayma, S.J., Professor of Philosophy 

 Stonyhurst College. Demy 8vo. cloth, los. 6d. 



Of the twelve Books into which this treatise is divided, the first 

 and second give the demonstration of the principles which bear 

 directly on the constitution and the properties of matter. The next 

 A 2 



