104 



THE WOODSMAN S HANDBOOK. 



scale. These scales are struck from the same center and meet at 

 a zero point, from which they are graduated outward in degrees to 

 90. A measuring arm, having a spatulate lower end beveled to 

 receive vernier graduations, sweeps these scales. This arm is car- 

 ried by a short shaft journaled in the upper edge of the plate and 

 concentric with the two curved scales. The outer end of the shaft 

 is furnished with a knurled handwheel, by which the clinometer 

 is operated. The inner end of the shaft carries a frame supporting 

 the tubular case containing the spirit tube of the hand level, the 

 center of the case being cut away to show the bubble in the tube. 

 A jam nut for setting the instrument is applied to the extreme 

 inner end of the shaft, and when turned inward holds the same 



FIG. 11. Combined surveyor's hand level and clinometer. 



against turning. The measuring arm and frame are rigid with the 

 shaft, so that when the same is turned in either direction they turn 

 together and to the same extent, the same as if of one piece. The 

 case stands at a right angle to the measuring arm, so that when the 

 arm is placed at the zero point of the two scales the case will be 

 exactly parallel with the longitudinal axis of the hand level. 



A slot formed in the top of the main tube is located in line below 

 the exposed middle portion of the spirit tube and in line above 

 the mirror, and permits the bubble to be reflected in the mirror, 

 which is so narrow and placed so close to the off side of the main 

 tube that it does not interfere with the line of vision through the 

 same and a view of the cross wire. 



