they have their name as plane sections of a cone. This method is calculated to produce a material simplification in these curves, and to make the proof of their properties more easily understood and remembered. It is also a powerful instrument in the solution of a large class of problems relating to these curves.

Jellet (John H.)—A TREATISE ON THE THEORY OF FRICTION. By JOHN H. JELLET, B.D., Senior Fellow of Trinity College, Dublin; President of the Royal Irish Academy. 8vo. 8s. 6d.

The theory of friction is as truly a part of Rational Mechanics as the theory of gravitation. This book is taken up with a special investigation of the laws of friction; and some of the principles contained in it are believed to be here enunciated for the first time. The work consists of eight Chapters as follows:-I. Definitions and Principles. II. Equilibrium with Friction. III. Extreme Positions of Equilibrium. IV. Movement of a Particle or System of Particles. V. Motion of a Solid Body. VI. Necessary and Possible Equilibrium. VII. Determination of the Actual Value of the Acting Force of Friction. VIII. Miscellaneous Problems— 1. Problem of the Top. 2. Friction Wheels and Locomotives. 3. Questions for Exercise. "The work is one of great research, and will add much to the already great reputation of its author."-SCOTSMAN.

Jones and Cheyne.-ALGEBRAICAL EXERCISES. Progressively arranged. By the Rev. C. A. JONES, M. A., and C. H. CHEYNE, M.A., F.R.A.S., Mathematical Masters of Westminster School. New Edition. 18mo. cloth. 2s. 6d.

This little book is intended to meet a difficulty which is probably felt more or less by all engaged in teaching Algebra to beginners. It is, that while new ideas are being acquired, old ones are forgotten. In the belief that constant practice is the only remedy for this, the present series of miscel laneous exercises has been prepared. Their peculiarity consists in this, that though miscellaneous they are yet progressive, and may be used by the pupil almost from the commencement of his studies. The book being intended chiefly for Schools and Junior Students, the higher parts of Algebra have not been included.

Kitchener.-A GEOMETRICAL NOTE-BOOK, containing Easy Problems in Geometrical Drawing preparatory to the Study of Geometry. For the Use of Schools. By F. E. KITCHENER, M.A., Mathematical Master at Rugby. New Edition. 4to. 2s.

It is the object of this book to make some way in overcoming the difficulties of Geometrical conception, before the mind is called to the attack of Geometrical theorems. A few simple methods of construction are given; and space is left on each page, in order that the learner may draw in the figures.

Morgan.-A COLLECTION OF PROBLEMS AND EXAM

PLES IN MATHEMATICS. With Answers. By H. A.
MORGAN, M.A., Sadlerian and Mathematical Lecturer of Jesus
College, Cambridge. Crown 8vo. cloth. 6s. 6d.

This book contains a number of problems, chiefly elementary, in the Mathematical subjects usually read at Cambridge. They have been selected from the papers set during late years at Jesus College. Very few of them are to be met with in other collections, and by far the larger number are due to some of the most distinguished Mathematicians in the University.

Newton's PRINCIPIA.

Edited by Professor Sir W. THOMSON 31s. 6d.

and Professor BLACKBURN. 4to. cloth.

It is a sufficient guarantee of the excellence of this complete edition of Newton's Principia that it has been printed for and under the care of Professor Sir William Thomson and Professor Blackburn, of Glasgow University. The following notice is prefixed :—" Finding that all the editions of the Principia are now out of print, we have been induced to reprint Newton's last edition [of 1726] without note or comment, only introducing the Corrigenda' of the old copy and correcting typographical errors. The book is of a handsome size, with large type, fine thick paper, and cleanly cut figures, and is the only modern edition containing the whole of Newton's great work. Undoubtedly the finest edition of the text of the Principia' which has hitherto appeared."-EDUCATIONAL TIMES.

66

6

Parkinson.-Works by S. PARKINSON, D.D., F.R.S., Fellow and Tutor of St. John's College, Cambridge.

Parkinson-continued.

AN ELEMENTARY TREATISE ON MECHANICS. For the Use of the Junior Classes at the University and the Higher Classes in Schools. With a Collection of Examples. Fourth edition, revised. Crown 8vo. cloth. 9s. 6d.

In preparing this work the author's object has been to include in it such portions of Theoretical Mechanics as can be conveniently investigated without the use of the Differential Calculus, and so render it suitable as a manual for the junior classes in the University and the higher classes in Schools. With one or two short exceptions, the student is not presumed to require a knowledge of any branches of Mathematics beyond the elements of Algebra, Geometry, and Trigonometry. Several additional propositions have been incorporated in the work for the purpose of rendering it more complete; and the collection of Examples and Problems has been largely increased.

A TREATISE ON OPTICS.

Crown 8vo. cloth.

IOS. 6d.

Third Edition, revised and enlarged.

A collection of examples and problems has been appended to this work, which are sufficiently numerous and varied in character to afford useful exercise for the student. For the greater part of them, recourse has been had to the Examination Papers set in the University and the several Colleges during the last twenty years.

Phear.-ELEMENTARY HYDROSTATICS. With Numerous Examples. By J. B. PHEAR, M. A., Fellow and late Assistant Tutor of Clare College, Cambridge. Fourth Edition. Crown 8vo. cloth. 5s. 6d.

This edition has been carefully revised throughout, and many new illustrations and examples added, which it is hoped will increase its usefulness to students at the Universities and in Schools. In accordance with suggestions from many engaged in tuition, answers to all the Examples have been given at the end of the book.

Pratt.-A TREATISE ON ATTRACTIONS, LAPLACE'S

FUNCTIONS, AND THE FIGURE OF THE EARTH.
By JOHN H. PRATT, M.A., Archdeacon of Calcutta, Author of
"The Mathematical Principles of Mechanical Philosophy." Fourth
Edition. Crown 8vo. cloth. 6s. 6d.

The author's chief design in this treatise is to give an answer to the question, “Has the Earth acquired its present form from being originally in a fluid state?" This Edition is a complete revision of the former ones.

Puckle.-AN ELEMENTARY TREATISE ON CONIC SECTIONS AND ALGEBRAIC GEOMETRY. With Numerous Examples and Hints for their Solution; especially designed for the Use of Beginners. By G. H. PUCKLE, M.A., Head Master of Windermere College. New Edition, revised and enlarged. Crown 8vo. cloth. 7s. 6d.

The

This work is recommended by the Syndicate of the Cambridge Local Examinations, and is the text-book in Harvard University, U.S. ATHENÆUM says the author " displays an intimate acquaintance with the difficulties likely to be felt, together with a singular aptitude in removing them."

Rawlinson.-ELEMENTARY STATICS, by the Rev. GEORGE RAWLINSON, M. A. Edited by the Rev. EDWARD STURGES, M.A., of Emmanuel College, Cambridge, and late Professor of the Applied Sciences, Elphinstone College, Bombay. Crown 8vo. cloth. 4s. 6d. Published under the authority of Her Majesty's Secretary of State for India, for use in the Government Schools and Colleges in India.

Reynolds.-MODERN METHODS IN

ELEMENTARY

GEOMETRY. By E. M. REYNOLDS, M. A., Mathematical
Master in Clifton College. Crown 8vo.

3s. 6d.

This little book has been constructed on one plan throughout, that of always giving in the simplest possible form the direct proof from the nature of the case. The axioms necessary to this simplicity have been assumed without hesitation, and no scruple has been felt as to the increase of their number, or the acceptance of as many elementary notions as common experience places past all doubt. The book differs most from established teaching in its constructions, and in its early application of Arithmetic to Geometry.

Routh.-AN ELEMENTARY TREATISE ON THE DYNAMICS OF THE SYSTEM OF RIGID BODIES. With Numerous Examples. By EDWARD JOHN ROUTH, M.A., late Fellow and Assistant Tutor of St. Peter's College, Cambridge; Examiner in the University of London. Second Edition, enlarged. Crown 8vo. cloth. 14s.

In this edition the author has made several additions to each chapter. He has tried to make each chapter, as far as possible, complete in itself, so that all that relates to any one part of the subject may be found in the same place. This arrangement will enable every student to select his own order in which to read the subject. The Examples which will be found at the end of each chapter have been chiefly selected from the Examination Papers which have been set in the University and the Colleges in the last few years.