ing the foundations for telegraph posts (as shown in with the senior member of the firm, whilst the credit of some Figs 3, 7, and 8), flagstaffs, and the like. When used in con- of the applications of the principle is due to the junior mem- nection with tube wells a slightly modified arrangement… … of the tube instead of directly upon it, as in the case of the BUTLER’S RHEOSTAT. piles. In the center of a pluga hole is bored and tapped, which rests upon the plumbago and moves over its surface the driving has been completed. The male thread on the ex- without abrading it. This rheostat seems…
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