290 NEGBETTI AND ZA.MBEA, HOLBDRN VIADUCT, E.G., 



1149 Under-ground Theodolite for Mining, Surveying, Levelling, or Military Service 

 (fig 1149). Combining in one instrument, the conveniences of a Y or Dumpy Level, 

 Circumferenter, and a Theodolite. On the top of the vertical axis of the instrument 

 is a Compass with divided ring reading by verniers. On two sides of this 

 compass are Spirit Levels with the usual adjustments for Azimuth observations. 

 Attached to the limb of the instrument is a vertical divided circle, upon which is a 

 Telescope with Rackwork adjustment mounted in reversing and adjusting Ts. A 

 Spirit Level is placed upon the Telescope similar to a Theodolite. Vertical angles 

 are obtained and read off on the vertical divided circle by two arms and a vernier 

 scale attached to the axis of the Telescope. 



The Telescope has cross wires in the Eye Tube. Clamps and tangent screws 

 are attached to the horizontal and vertical movements. Tripod Stand and mahogany 

 box for the instrument Price . 22 



Plain Sights to fit on the Compass box or Telescope, Astronomical and 

 Diagonal Eye Pieces, Dark Glass Caps for Sun observations, supplied to order at 

 an extra cost. 



CIRCUMFERENTERS, OR MINER'S DIALS, CROSS SIGHTS, ETC. 



s. d. 



1150 Circumferenter, or Miner's Dial, 4-inch Ordnance pattern, divided 



and figured on raised rim to 360, and also the quarters figured below 

 to 90, folding sights, ball-and-socket joint with clamping screws, 

 bar needle and agate centre, the dial lettered the same as a Theodolite, 

 jointed legs. In 2 cases for compass and stand . . . .770 



1151 Ditto ditto, 5-inch, with Cross Levels 880 



1152 Circumferenter, 5 -inch, with rackwork adjustment and vernier to dial, 



bar needle, folding sights, ball-and-socket joint, divided cover for vertical 

 angles, jointed legs, complete in two cases . . . . .990 



1153 Circumferenter, 6-inch, with rackwork adjustment and vernier to dial, 



bar needle, folding sights, divided cover for hypo and base, cross levels, 

 with tripod staff, jointed extra points for use at half length, and ball-and- 

 socket joint with plummet, &c., in two cases complete (fig. 1153) 12 12 



