164 



Diaphragm showing ar- 

 rangement of wires as used 

 with our mine transits, to 

 distinguish center horizon- 

 tal wire from stadia wires, 

 to avoid mistakes. 



Patented, 



Complete Mining Transit, 



With detachable Side Telescope and Beflector for illuminating cross wires, 

 AN made by < I. Berber & SODN. 



Size as in Nos. 5, 6 and 7. For price and attachments see page ir,-j. 



NOTE. The side telescope has been the more customary attachment to mining transits. It can be u 

 attached or detached from the instrument proper. It can be of the same length as the main telescope when so 

 ordered, but it is usual with us to make it an inch or so shorter, to keep it as light as possible, and to save weight in 

 the counterpoise. When the side telescope and its counterpoise are attached to the transverse axis, they MUinOI 

 each other, and therefore the adjustment of the line of collimation of the main telescope is not disturbed in he 

 vertical plane. The weight of the side telescope and its counterpoise is about i Ib. for i-.u h. 



It will be seen that in the mining transit illustrated above the hori/ontal remiers are placed at an angle of 35 

 to line of sight of telescope, to enable one to read the verniers in cramped places without stepping aside. Tli 

 plate level in this instrument is therefore of standard length and character, and in form is much improved on former 

 styles. This will be appreciated when it is remembered that this is the main level on the transit which governs the 

 movement of the line of collimation in a vertical plane. To place this level outside of the plates and in front ot 

 the telescope, as shown on page 148, is not permissible in mining transits, as it would shorten the range of th' 

 main telescope for steep sighting. 



An instrument having its front level placed as shown above might be accompanied by a striding level for best 

 results in steep sighting if style of instrument permits. If not permissible we can place an auxiliary level of standard 

 length on the main telescope, near the eye end, as shown in cut on opposite page, instead. 



