K50 



L. CASELLA'S CATALOGUE 



FIG. 370. 



FIG. 382*. 



use, its diagonal eye-piece admitting of zenith stars being observed with perfect 

 facility. It is supplied with a reflector for illuminating the wires at night, 

 a dark glass for solar observations, a finely divided level, a compass, and the 

 means of performing all the adjustments necessary in such instruments. It 

 packs in a mahogany case, 4 inches by 5 inches, and 6f inches long (outside 

 measure), the whole weighing only 3^1bs., a light tripod staff is also added. A 

 paper descriptive of the instrument was read at the meeting of the British 

 Association at Exeter, 1869, in section E, by Lt.-Col. A. Strange, F.K.S., Inspec- 

 tor of Scientific Instruments, India Department (fig. 370). . 15 15 



*#* For mining surveys where closer dividing, as well as angles below the base line, are re- 

 quired, the size of this instrument is increased to 4, 5, or 6 inch, circles, divided to 30 or 20 

 seconds, with larger telescope and compass in proportion, the handy portable character of the 

 instrument still being preserved ; the prices are 19 10s., 24, and 30. 



372. TEAVELLEE'S TEANSIT THEODOLITE, as above, with the telescope in centre, the 



supports being raised to allow it to revolve vertically. In this arrangement 

 though the height is increased, the zero or centre is found more exact in very- 

 close measurements, and an arrangement is added by which the horizontal circle 

 may be set to zero at each observation without disturbing the adjustment 



18 



373. Transit Theodolite^ 4-inch., with locking plate, etc., as 375, the circle divided on 



silver, with verniers reading to one minute, in mahogany case and tripod 

 stand, complete . . . . . 25 10 



374. TEANSIT THEODOLITE, 5-inch., verniers reading to 30 seconds, divided on silver, 



complete, with locking plate, as above. . . . 29 10 



375. TEANSIT THEODOLITE, 6-inch., with locking plate for stability, transit axis and 



vertical circle (may be used as an altitude and azimuth instrument), in 

 maho gany case, with tripod stand, complete (fig. 375), p. 58 34 10 



376. Transit Theodolite? as above, with illuminated axis, axis level and lantern 



38 



377. TEANSIT THEODOLITE, as above, with two telescopes . . 45 10 

 378. Transit Theodolite^ 7-inch., with transit axis and vertical circle, axis level and 



lantern, with tripod base, etc., as No. 375 above . . 43 10 



379. TEANSIT THEODOLITE, 8-inch., as above . . . 51 



