. The railroad and engineering journal . de of the tele-scope. The capstan-headed screws [/ U are made fast tothis ring, and by means of these screws the hairs can bemoved in order to adjust them. The telescope A A turns with ease in the wyes, and asit is necessary to have the bubble //always directly belowthe center line of the telescope, it is a good plan to get thebubble once in its proper place, and then make a scratchrunning from the telescope upon the wye ; then no timewill be lost in being sure the telescope is in its properposition, as it only has to be turned until the two ends ofthe
. The railroad and engineering journal . de of the tele-scope. The capstan-headed screws [/ U are made fast tothis ring, and by means of these screws the hairs can bemoved in order to adjust them. The telescope A A turns with ease in the wyes, and asit is necessary to have the bubble //always directly belowthe center line of the telescope, it is a good plan to get thebubble once in its proper place, and then make a scratchrunning from the telescope upon the wye ; then no timewill be lost in being sure the telescope is in its properposition, as it only has to be turned until the two ends ofthe scratch come together. On some of the more modern instruments there is alittle projection on the wye, and a corresponding one onthe telescope, and when these two are in contact the tele-scope is in its proper position. In the center of the tripod-head is a chain and hook, upon which a plumb-bob maybe hung when needed. Two Lining Rods are shown in Plate XIV, fig. i ; theyare such as are used with either a transit or a surveyors Pl^TE XIV. compass. They are rounder octagonal in shape, and from6 to 10 ft. long, I in. or ij in. in diameter at the bottom,and J in. or f in. in diameter at the top. They are dividedinto feet, the foot-spaces being painted red and white Vol. LXII, No. I.] ENGINEERING JOURNAL. II alternately. At the bottom the rods are shod with a steelshoe about i ft. long. These rods are made of white pineor any light suitable wood. Under some circumstancesthey are made of small gas-pipe, but if over 6 ft. longthese are too heavy for convenience. The Standard Level Rod is shown in Plate XIV, It is divided into feet, and these again into tenths of afoot. For convenience in use the rod is made in twoparts, the back part sliding upon the front, as two parts are clamped together by means of a milled-head screw. The target B is quartered red and white,and is made to slide up and down on the rod. When therod is closed the target is clamped in any position by
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