KEUFFEL & ESSER CO. 127 Fulton St., NEW YORK General Office and Factories, HOBOKEN, N.J. CHICAGO − ST. LOUIS − SAN FRANCISCO − MONTREAL _DRAWING MATERIALS_ _MATHEMATICAL and SURVEYING INSTRUMENTS_ _MEASURING TAPES_ ------------------------------------------------------------------------ [Illustration: 6 in. Standard with magnifying Cursor complete in pocket case, 5/-] NORTON & GREGORY LTD. Head Office CASTLE LANE, WESTMINSTER, LONDON, S.W. 1 Branches 71 QUEEN STREET, GLASGOW. PHOENIX HOUSE, QUEEN STREET and SANDHILL, NEWCASTLE-ON-TYNE. SLIDE RULES in Stock, from 17/6 to 27/6 Special Quotations to the Trade for Quantities For particulars of Surveying, Measuring and Mathematical Instruments, Appliances and Material of all kinds for the Drawing Office, write to the Head Office. [Illustration: NORTON & GREGORY LTD] ------------------------------------------------------------------------ NORTON & GREGORY, LTD., London. “DIAMOND” DRAWING INSTRUMENTS Manufactured at our London Works. CENTRE SCREW SPRING BOW HALF SET. [Illustration: [Centre Screw Spring Bow Half Set]] 4 inch Spring Bow Half Set centre screw adjustment, with interchangeable needle, pen, and pencil points Price 17/6 The Centre Screw Spring Bow Half Set of Compasses, as illustrated, possesses the advantage of COMBINING IN ONE INSTRUMENT THE SET OF THREE SEPARATE SPRING BOWS hitherto in use, while the centre screw makes for ease and accuracy of manipulation, at the same time providing a radius of over 2 inches, or double that of the old pattern. This instrument is less expensive than the set of 3 bows, while considerably stronger in construction. The fixed needle point is shouldered. This illustration is given as an indication of the various Drawing Instruments manufactured by us. Illustrated Booklet giving full particulars and prices of other Instruments and Cases of Instruments sent on application. Specially arranged Sets of Instruments made for Colleges, Schools, Technical Institutes Estimates submitted on Application. _Write to our Head Office_: CASTLE LANE, WESTMINSTER, LONDON, S.W. 1. ------------------------------------------------------------------------ DRAWING AND SURVEYING INSTRUMENTS