AND EDUCATIONAL SERIES. The following are the Works already published in ARITHMETIC, MATHEMATICS, &c. (The Volumes are bound in limp cloth, except where otherwise stated.) MATHEMATICAL INSTRUMENTS, a Treatise on; in which their Construction, and the Methods of Testing, Adjusting, and Using them are concisely Explained. By J. F. HEATHER, M.A., of the Royal Military Academy, Woolwich. Original Edition, in 1 vol., Illustrated. 18. 6d. . In ordering the above, be careful to say Original Edition," or give the number in the Series (32) to distinguish it from the Enlarged Edition in 3 vols., advertised on the back Cover. a LAND AND ENGINEERING SURVEYING, Treatise on; with all the Modern Improvements. Arranged for the Use of Schools and Private Students; also for Practical Land Surveyors and Engineers. By T. BAKER, C.E. Illustrated with Plates and Diagrams. 2s. SUBTERRANEOUS SURVEYING, Elementary and Practical Treatise on, with and without the Magnetic Needle. By THOMAS FENWICK, Surveyor of Mines, and THOMAS BAKER, C.E. Illustrated. 2s. 6d. READY RECKONER FOR THE ADMEASUREMENT OF LAND. By ABRAHAM ARMAN, Schoolmaster, Thurleigh, Beds. To which is added, a Table showing the Price of Work, from 2s. 6d. to £1 per acre, and Tables for the Valuation of Land, from 1s. to £1,000 per acre, and from one pole to two thousand acres in extent, &c. &c. 1s. 6d. DESCRIPTIVE GEOMETRY, an Elementary Treatise on; with a Theory of Shadows and of Perspective, extracted from the French of G. MONGE. To which is added a Description of the Principles and Practice of Isometrical Projection; the whole being intended as an Introduction to the application of Descriptive Geometry to various branches of the Arts. By J. F. HEATHER, M.A. Illustrated with 14 Plates. 2s. COMMERCIAL BOOK-KEEPING. With Commer cial Phrases and Forms in English, French, Italian, and German. By JAMES HADDON, M.A.. Arithmetical and Mathematical Master of King's College Sch LOCKWOOD & CO. A SELECTION FROM WEALE'S SERIES. ARITHMETIC, a Rudimentary Treatise on with full Explanations of its Theoretical Principles, and numerous Examples for Practice. For the use of Schools and for Self- Instruction. By J. R. YOUNG, late Professor of Mathematics in Belfast College. New Edition, with Index. 1s. 6d. A KEY to the above, containing Solutions in full to the Exercises, together with comments, explanations, and improved EQUATIONALE ARITHMETIC, applied to Questions of Interest, Annuities, Life Assurance, and General Commerce; with various Tables by which all Calculations may be greatly facilitated. By W. HIPSLEY. In two parts, 1s. each; or in one ALGEBRA, the Elements of. By JAMES HADDON, M.A. With Appendix containing miscellaneous Investigations, and a Collection of Problems in various parts of Algebra. 2s. A KEY and COMPANION to the above Book, forming an extensive repository of Solved Examples and Problems in Illus- tration of the various expedients necessary in Algebraical opera- EUCLID, the Elements of: with many additional Propo- sitions, and Explanatory Notes; to which is prefixed an Intro- SPHERICAL TRIGONOMETRY, the Elements of. By JAMES HANN. Revised by CHARLES H. DOWLING, C.E. 18. Or with the Elements of Plane Trigonometry, in one volume, 28. MENSURATION AND MEASURING, for Students and Practical Use. With the Mensuration and Levelling of Land for the purposes of Modern Engineering. By T. BAKER, |