_A Practical Treatise on the Science of Land and Engineering Surveying, Levelling, Estimating Quantities, etc._, with a general description of the several Instruments required for Surveying, Levelling, Plotting, etc. By H. S. MERRETT. Third edition, _41 plates with illustrations and tables_, royal 8vo, cloth, 12_s._ 6_d._ PRINCIPAL CONTENTS: Part 1. Introduction and the Principles of Geometry. Part 2. Land Surveying; comprising General Observations -- The Chain -- Offsets Surveying by the Chain only -- Surveying Hilly Ground -- To Survey an Estate or Parish by the Chain only -- Surveying with the Theodolite -- Mining and Town Surveying -- Railroad Surveying -- Mapping -- Division and Laying out of Land -- Observations on Enclosures -- Plane Trigonometry. Part 3. Levelling -- Simple and Compound Levelling -- The Level Book -- Parliamentary Plan and Section -- Levelling with a Theodolite -- Gradients -- Wooden Curves -- To Lay out a Railway Curve -- Setting out Widths. Part 4. Calculating Quantities generally for Estimates -- Cuttings and Embankments -- Tunnels -- Brickwork -- Ironwork -- Timber Measuring. Part 5. Description and Use of Instruments in Surveying and Plotting -- The Improved Dumpy Level -- Troughton’s Level -- The Prismatic Compass -- Proportional Compass -- Box Sextant -- Vernier -- Pantagraph -- Merrett’s Improved Quadrant -- Improved Computation Scale -- The Diagonal Scale -- Straight Edge and Sector. Part 6. Logarithms of Numbers -- Logarithmic Sines and Co-Sines, Tangents and Co-Tangents -- Natural Sines and Co-Sines -- Tables for Earthwork, for Setting out Curves, and for various Calculations, etc., etc., etc. _Saws: the History, Development, Action, Classification, and Comparison of Saws of all kinds._ By ROBERT GRIMSHAW. _With 220 illustrations_, 4to, cloth, 12_s._ 6_d._ _A Supplement to the above_; containing additional practical matter, more especially relating to the forms of Saw Teeth for special material and conditions, and to the behaviour of Saws under particular conditions. _With 120 illustrations_, cloth, 9_s._ _A Guide for the Electric Testing of Telegraph Cables._ By Capt. V. HOSKIŒR, Royal Danish Engineers. _With illustrations_, second edition, crown 8vo, cloth, 4_s._ 6_d._ _Laying and Repairing Electric Telegraph Cables._ By Capt. V. HOSKIŒR, Royal Danish Engineers. Crown 8vo, cloth, 3_s._ 6_d._ _A Pocket-Book of Practical Rules for the Proportions of Modern Engines and Boilers for Land and Marine purposes._ By N. P. BURGH. Seventh edition, royal 32mo, roan, 4_s._ 6_d._ _Table of Logarithms of the Natural Numbers, from 1 to 108,000._ By CHARLES BABBAGE, Esq., M.A. Stereotyped edition, royal 8vo, cloth, 7_s._ 6_d._