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Pocket Leveling: Instrument with Divided Circle.* 



In the ordinary practice of the Builder, Agriculturalist, Gardener, etc., etc. ; it 

 Is often necessary to obtain relative positions and heights, within practical limits. For 

 such needs we offer this instrument at once well made, reliable and low in price. 



This instrument, shown on the opposite page, has the unusual advantage that the level bubble, cross 

 wires and images can all be seen at a glance, since the bubble of the level can be seen from within the tele- 

 scope and not from without. The bubble is somewhat magnified by the power of the eye-piece, and on this 

 account the efficiency of the instrument is considerably raised and very much surpasses the old-fashioned water 

 level. At the same time the handling; of it is so simple that those who do not know how to work with the 

 ordinary level and telescope may readily become adept in its use. In the sectional view opposite, the inner 

 arrangement can clearly be seen. The telescope has a magnifying power of 5 diameters, the objective is achro- 

 matic, but the eye-piece has only a single lens. 



The instrument can be mounted on any convenient support, while for approximate results, with a little 

 practice, it may even be held in the hand. In order to obtain a stable mounting, it can be placed on a tripod 

 or Jacob-staff, or can be screwed to a bench, window-sill, or other convenient support. By means of the ball 

 and socket joint above the fastening screw, the instrument can be approximately placed in a horizontal plane. 



In order to see the image and cross-wires of the telescope distinctly, the eye-piece slide must first be 

 moved out or in till the wires are very sharply defined, then by turning the focussing screw move the main tube 

 out or in till the image of the object sighted at also becomes very distinct. For distances of 60 feet or so the 

 main tube should be moved out till the mark on the tube just shows. For shorter distances the tube must 

 be moved out farther, and for longer distances moved in slightly, till in each case the imatre is distinct. 

 This la;t process can best be done by taking the instrument from the center and holding it in the hand. A 

 shown by the cut opposite, there is a mirror with a hole in the center, placed at an angle of 45 inside the 

 main slide tube. Below this mirror is the level, which has two adjusting screws. Through the opening in the 

 bottom of the level tube light passes, .illuminating the mirror, and when the instrument is horizontal, by look- 

 ing through the eye-piece, the bubble can be seen in a vertical position and at the same time the image and 

 cross-wires can be seen. 



In order to obtain a horizontal position of the instrument it is necessary to operate the milled-head nut 

 under the object-glass until the image of the bubble shall appear to the eye as much above the cross wire 

 opening as it does below the same, as illustrated by the small cut opposite. Of course for every change in position 

 in the horizontal plane, the bi-section of the bubble must be verified. The eye should be placed very close to 

 the eye-piece so as to be able to observe the whole mirror surface. Near sighted persons, who, on account of 

 their glasses, cannot bring the eye near to the eye-piece, should take the cross-wire opening as the mark and 

 watch for the bubble above and below the same. In case the instrument is in a building where the light is 

 poor, the bubble may be sufficiently illuminated by a piece of white paper or the bare hand held beneath the 

 level tube. 



Price, as above, with terrestrial telescope, horizontal circle reading to minutes, 

 in Morocco Pocket Case, and light tripod, $32.OO 



Pocket Leveling Instrument with Reversion Level.* 



This instrument, fitted with a reversion level, has as compared with other designs 

 provided with a striding level, the important advantage that it dispenses with the incon- 

 venience of adjusting the level, also with the reversing of the telescope in its wyes. 



The telescope magnifies 12 times ; its definition is such that less than one-half an inch can be read off at 

 a distance of 300 feet. The degree of accuracy is YTTTJT'TT f tne distance. 



The reversion level is encased and protected from external influences ; the bubble is directly visible in 

 the field of the eye-piece, the whole is mounted on a light tripod with a ball and socket joint. 



NOTE. This instrument, which is intended for accurate measurements, can be used without preliminary 

 adjustment. The manipulation is very simple, and is done thus : set up the instrument with the level on the 

 left and take a reading; unscrew the milled-headed screw by which it is fastened to the horizontal bar carry- 

 ing the micrometer screw ; turn the instrument upside down with the level on right and fasten in place ; take 

 another reading and tne arithmetical mean is the correct value. 



Price, including: Pocket Case, $42.OO 

 The Road Builder's Dumpy Level 



has been designed by us to meet a growing want for the road builder as well as for 

 the drainage engineer. The degree of accuracy obtained with it is commensurate 

 with the work required. It will not be as accurate as cur 15 or IS inch Dumpy Lcvrl. 

 but we believe it will be quite satisfactory in the above cases, where a lighter and 

 cheaper instrument is desirable. 



The telescope is 12 inches long, is erecting, and has an aperture of i% inches and a power of 24 diameters. 

 The eye-piece is provided with an improved screw arrangement for the accurate focussing of cross- \s i r<--< ; 

 field of view large and flat; objects erect ; telescope balanced eachivav from the center ivhen focussed to a 

 mean distance -with tttn-thadt attached to it; the center is very stout, "loni; and of the hardest belt-metal ; 5!^ 

 inch very sensitive spirit level ; instrument does not detach from tripod above leveling screws; it packs whole 

 and stands in the c.ise erect. Mahogany case, provided with straps and hooks, contains sun-shade, wrench, 

 screwdriver, and adjusting pin. 



The above instrument, being of the Dumpy level type, has to be adjusted by the two peg method 

 as described in our manual (p. 54; for the Dumpy Level. 



Weight of instrument 7 !!>>., woight of tripod from <5 to 7 Ibs. 



fir-.ss w.-ihr "f Ingtmment, paeked securely for shipment in two boxes, about Mli>s. 



Prico, //'/ Klin'iprnt.crttnntn the object-slide, $75. OO 



i:\1rsis: Stadia wires, 8.00 



r li;iir, 1 nl) 



r.'t tie of fine oil, . . . . .25 



** Not of our manufacture. 



