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168. DRAWING AND MEASURING INSTRUMENTS. Including - I. Instruments employed in Geometrical and Mechanical Drawing, and in the Construction, Copying, and Measurement of Maps and Plans. II. Instruments used for the purposes of Accurate Measurement, and for Arithmetical Computations. By J. F. Heather, M.A., late of the Royal Military Academy, Woolwich, Author of " Descriptive Geometry," etc, etc. Illustrated, Is. 6d.

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227. MATHEMATICS AS APPLIED TO THE CONSTRUC-

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