compasses are formed with floating paper valve to press it firmly against its seat; the wedge cards. The magnetic needle is cemented on the cases. being loosened before the valve is withdrawn. The patent for this invention was granted through underside of the card, and it is pivoted at the center… … A vertical section of the apparatus is shown in focus. The lens is mounted in an india-rubber disk, which is operated by pressing with the finger on the at the upper end of a brass tube, and the tube is pro- Fig. 1. Ais the pipe through which the water flows nib, c. Major Myer, signal officer in…
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