MATHEMATICS. 



cules is investigated and determined : and by it the general properties of 

 todies are explained. The eighth book treats of luminiferous (zther. The 

 ninth explains some special properties of bodies. The tenth and eleventh 

 contain a radical and lengthy investigation of chemical principles and 

 relations, which may lead to practical results of high importance. The 

 twelfth and last book treats of molecular masses, distances, and powers. 



Beasley. AN ELEMENTARY TREATISE ON PLANE 

 TRIGONOMETRY. With Examples. By R. D. BEASLEY, 

 M. A., Head Master of Grantham Grammar School. Second 

 Edition, revised and enlarged. Crown 8vo. cloth. 3-r. 6d. 

 This treatise is specially intended Jor use in schools. The choice of matter 

 has been chiefly guided by the requirements of the three days' examination 

 at Cambridge. A bout four hundred examples have been added to this edition, 

 mainly collected from the examination papers of the last ten years. 



Boole. Works by G. BOOLE, D.C.L., F.R.S., Professor of 

 Mathematics in the Queen's University, Ireland. 



A TREATISE ON DIFFERENTIAL EQUATIONS. New and 

 Revised Edition. Edited by I. TODHUNTER. Crown 8vo. cloth. 

 I4f. 



Professor Boole has endeavoured in this treatise to convey as complete an 

 account of the present state of knowledge on the subject of Differential Equa- 

 tions, as was consistent with the idea of a work intended, primarily, for 

 elementary instruction. The earlier sections of each chapter contain that 

 kind of matter which has usually been thought suitable for the beginner, 

 while the latter ones are devoted either to an account of recent discovery, or 

 the discussion of stick deeper questions of principle as are likely to present 

 themselves to the reflective student in connexion -with the methods and 

 processes of his previous course. 



A TREATISE ON DIFFERENTIAL EQUATIONS. Supple- 

 mentary Volume. Edited by I. TODHUNTER. Crown 8vo. cloth. 

 8s. 6d. 

 This volume contains all that Professor Boole -wrote for the purpose of 



enlarging his treatise on Differential Equations. 



