(with a copy of Rules, Tables and Formulae for Patent Circular Slide Rule, both in fitted leather-covered case (defective); A military-pattern bakelite prismatic compass (defective); and a small Czechoslovakian early 20th century postal balance - 12.5cm. high " /> (with a copy of Rules, Tables and Formulae for Patent Circular Slide Rule, both in fitted leather-covered case (defective); A military-pattern bakelite prismatic compass (defective); and a small Czechoslovakian early 20th century postal balance - 12.5cm. high " /> BRITISH ANTARCTIC EXPEDITION, 1910-1914 , George Murray Levick's surveying and other instruments comprising: A fine English early 20th century lacquered brass air-flow meter, by <I>Negretti & Zambra, London No 1216</I>, further marked on the base <I>Lowne's Silver Medal Air Meter</I>, the silvered dial raised on 3 turned brass pillars andgraduated <I>0-100 Feet</I>, with subsidiary dials for <I>HDS'</I>, <I>THDS'</I>, <I>10THDS'</I>, <I>100THDS'</I>, and <I>MILLNS'</I>, driven by an 8-bladed aluninium fan, the base threaded for the mounting bracket, in a fitted mahogany case with brass handle, printed label with manuscript insertions pasted inside cover: 'International Inventions Exhibition Awarded Siver Medal. Correction for Air Meter No. 1216 Add 30 per minute to the observed reading of the Air Meter' (<I>paint slightly chipped on fan struts, crack on base of case</I>) -- <I>8.5cm. high</I>; [<I>with:</I>] 3 drawing sets, in fitted cases; An early 20th century nickel plated double-sided circular slide rule, marked on the dial <I>Halden's "Calculex"</I> (with a copy of <I>Rules, Tables and Formulae for Patent Circular Slide Rule</I>, both in fitted leather-covered case (<I>defective</I>); A military-pattern bakelite prismatic compass (<I>defective</I>); and a small Czechoslovakian early 20th century postal balance - <I>12.5cm. high</I> | Christie's