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Illustrated catalogue and price-list of drawing and tracing papers, sun print papers and equipments, drawing instruments and materials, surveying instruments, accessories, etc / Kolesch & Company. . The improvement consists, first, in a rearrangement of the workswhich admits of the column carrying the arms and cups, rising fromthe center of the base, and secondly, an arrangement by which the enu-meration is affected by two hands which can be set to zero on the com-mencement of an observation, thus obviating the necessity of taking areading of the dials before proceeding to make a fresh observa
Illustrated catalogue and price-list of drawing and tracing papers, sun print papers and equipments, drawing instruments and materials, surveying instruments, accessories, etc / Kolesch & Company. . The improvement consists, first, in a rearrangement of the workswhich admits of the column carrying the arms and cups, rising fromthe center of the base, and secondly, an arrangement by which the enu-meration is affected by two hands which can be set to zero on the com-mencement of an observation, thus obviating the necessity of taking areading of the dials before proceeding to make a fresh observation. Another improvement is the recent introduction of ball-bearings tothe central shaft by which the friction is reduced to a minimum and thewearing of the instrument prevented. 8071 Robinsons Anemometer as above, with 3 inch cups, reading to 500 miles, complete .each, $ 270 KOLESCH <fe CO. &*K\ NEW YORK. The Portable Current This instrument is constructed and used for the measurement of rate or flow ofsmall rivers and streams, also for the flow of tides. For this purpose the meter should be placed in the stream, as per directions sup-plied, and allowed to run for a given time. The rate of the stream per unit time isthen shown by reference to the graduations of the circles which are actuated by theforce of the water upon the Fan-screw. The value of the graduation is as follows: i. The inner circle, graduated to show 8 miles in a revolution. 2. Each mile, subdivided into 8 parts, showing furlongs. 3. Each furlong graduation, subdivided into 3 parts, equal to 220 feet each. 4. The outer circle, graduated to show single feet, and a complete revolution 220 feet. m The circles B are attached to a movable arm, which throws the endless screw inor out of gear. This arm can be raised by turning the screw which passes through thecoil spring E, which would fix the gearing for constant use. It can also be raised bypul
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Keywords: ., bookcentury1900, bookdecade1910, bookidillustratedc, bookyear1917