The sighting tube A A´ is 14 in. long and has at the end A´ a pin hole looking through the tube, and at the other end A a small ring inside the brass shield or outer ring shown in cut holding the cross wires. A cover is provided as shown in cut to protect the cross wires. This tube rests in the Ys, Y and Y´. On this tube at the Ys are two rings with flanges, like car wheels, and it is held in its place by the latches on the top of the Ys. By loosening these latches this sighting tube may be revolved to test the adjustment of the cross wires.
At the feet of the Ys will be seen the nuts, one above and one below the end of the cross bar, which may be turned, thus raising or lowering the end of the tube and adjusting the line of sight to the line of level. The circle C is graduated to 10° and the pointer marked to degrees, so that the instrument may be used in laying off angles, squaring foundations, &c. The pointer is movable and can be fixed in position by the set screw shown in the cut just below the cross bar. The cross bar carries the glass bubble which is seen in the cut. The bubble itself may be adjusted by the screws. To the circle are attached the two thumb screws and springs opposite to them by means of which the instrument is brought to a level.
In the outer edge of the Base B is a smoothly turned groove in which the feet of the screws and springs may slip easily whenever it may be necessary to revolve the circle on the base. The centre of the base is formed into a socket for the ball referred to above. The under surface has a solid cylinder which screws in the collar of the tripod. The cord suspending the plumb-bob drops from the centre of the instrument to which it is attached by a loop not shown in the cut. From this description it will be seen that this instrument can be adjusted in every way possible in the highest priced instruments, and has besides the additional feature of a horizontal circle, making it in reality a plain transit, as well as level.
Every instrument will be completely adjusted before it is shipped.
The instrument is put up in a handsome wooden box with strap for carrying and furnished with a surveyor’s tripod and a short or mason’s tripod.
PRICE OF INSTRUMENT COMPLETE, $20.
Forwarded by express on receipt of price. The charges of transportation from New York to the purchaser are in all cases to be borne by him, I guaranteeing the safe arrival of all instruments to the extent of express transportations, and holding the express companies responsible to me for all losses or damages on the way.
A NEW LEVELING ROD.
This rod is round and made in two sections, so that it can be conveniently carried, is united by a solid screw joint, so that when together it is as firm as if of one length, and has a target as shown in illustration, made to slide on the rod.