112 



Engineers' and Surveyors' Transit. 



This instrument i* designed tor eiio-ineerin work of a high class, such as is 

 required in bridge building, water works, andfor city and land surveying. The 

 size of the circle is such that it maybe graduated to read to 30* or 20* without 

 fatigue to the eve. The telescope is of the best definition, and has a large apertmv 

 with perfectly fat Held. The eyepiece is achromatic, and gives a larg'c lidd with 

 plenty ot light. AVr advise our customers to order .W/V silver graduations for this 

 instrument, also ground glass shades over the verniers for reasons given on page (5. 



Transits Xo. 1 No. 1 c. Horizontal circle G% in. (ed-.- of -raduafioin 

 two double verniers readicg to minutes; two rows of figures in opposite directions 



from ii to :!W : figures on limb and verniers are inclined in the direction they should 

 be read: verniers and graduations are protected with line plate <dass and provided 

 with glass shades ; graduations are silvered ^ magnetic needle 4y 2 inches; <i<ljuxt,,,vHt, 

 for vertical plane of telescope; improved spring tangent screw, impro\ed lower 

 gent screw; shifting center to set the instrument exactly over a <jiven point ; impro\erl 

 telescope 11 .y 2 inches long ; objects erect ; aperture 1% inches ; power of the telescope 

 :H dia.. which qualifies it especially for telemeter work ; eye-piece is provided with ;m 

 improved screw arrangement for the accurate focussing of cross-wires: telescope is 

 perfectly balanced and reverses at both ends ; spirit-levels ground and extra sensitive : 

 line of collimation correct for all distances without adjustable object -slide : protect ion 

 to object-slide ; long compound centers with heavy flanges ; improved split-lea tripod 

 with thumb-nuts. 



The mahogany case has a leather strap, hooks, etc. It contains a sun-shade, a 

 wrench, a screw driver, an adjustable plumb-bob, a magnifying glass, and 



adjusting pin, and weighs from D^ to 10 Ibs. 



Weight of Plain Transit, (No. 1), ' . . . 13U Ibs. 1 

 " " Transit with Level Attachment, (No. 1 a) 14 " L 

 " > ; Complete Transit, (No. 1 b and No. 1 c) 14^ " J lroia 7 to 7 % lbs * 

 Gross weight of instrument, complete, packed securely for shipment in 2 boxes. 



ibout 50 lbs. 



Extras to Transits No. 1 No. Ic inclusive. 



Graduation of horizontal circle, on solid silver 10.00 



" " reading to 30" 10.00 



20" 20.00 



Graduation of vertical arc or vertical circle, on solid silver .... 5.00 



Gradienter attachment (see page 39) . . . .... 5.00 



Stadia Wires, fixed 3.00 



Short Focus Lens (pages 118, 169 \ One pair 16.00 



Richards Prism, attachable to our complete Transits or Levels (see page 



85 of Manual) 30.00 



Arrangement for off net ling at right angles . 5.00 



Aluminum guard for the full vertical circle (see page 146^! . . . 4.00 



Variation plate 10.00 



Silk hood* to cover transit in case of rain or dust, .... . 1.00 



Bottle of fine watch-oil to lubricate the centers, etc., of transit . . . o. _'."> 



NOTE. Sometimes we are asked by those not intimately acquainted with the principles governing a tele- 

 scope to place a higher power than is customary with the best makers upon a telescope of the size describe* 1 

 above. In answer we wish to say that with the power mentioned above very good results in stadia measurement 

 can be obtained, and that while the power could be easily increased, the light and definition of the telescope 

 would become so diminished that it would render the instrument less efficient in more than one respect. In this 

 connection we refer to the various articles written on the telescope in part I. of catalogue. In some cases, how- 

 ever, where the instrument i* principally it.cended for use in stadia measurements, we can increase the aperture 

 of our inverting telescope for Transits No. 1 from I'.j to 1 '' inches diameter. This increase in aperture will 

 permit of a hizher power. Thus two eye-pieces, magnifying respectively '<?7 and 33 diameters, can be supplied 

 with such a telescope; but the danger of the wires getting broken, or dust blowing into the telescope, etc., m 

 charging the eye-pieces, is so great, that in instruments of the above class the use of two <ye-pieces shmild 

 be as little resorted to as possible. To increase the aperture of the object-glass to 1? ii/ohes adds $ 10.00 t<> 

 the cost of the instrument, and where both eye-pieces are ordered an extra charge of $5.00 will be made. 

 ;ange in aperture will add about 10 o/. to the weight of the instrument. No extra charge if telescope 

 ie to be of the inverting kind, but the instrument must be made specially. 



*Silk is used in place of gossamer waterproof, because the latter contains sulphur which tarnishes the 

 silver graduations. If a heavier cover is wanted, we advise the UM- <>) t\\<> hoods, one over the other. 



