76 BENJ. PIKE'S, JR., DESCRIPTIVE CATALOGUE. 



Fig. 98. 



the barrel. H is the telescope; adapted to the instrument 

 in a manner similar to that of the sextant. I and J are two 

 handles fixed parallel to the plane of the circle, and a third 

 handle, K, is screwed on at right angles to that plane, and 

 can be transferred to the opposite face of the instrument 

 by screwing it into the handle, I ; the use of this extra 

 handle is for convenience in reading and in holding the in- 

 strument, when observing angles that are nearly horizontal ; 

 it can be shifted, according as the face of the instrument is 

 held upwards or downwards. The requisite dark glasses 

 are attached to the frame-work of the circle, to be used in 

 the same manner and for the same purposes as those of the 

 sextant. With respect to the adjustments and application 

 of this instrument, we cannot do better than use the words 



