Saving Labor in Measuring Heights 



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Figure 1 



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lO'foli 



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Figure 2 





Figure 3 



A second pivot and pendulum are attached to a block that is 

 made to slide in a groove along the entire length of the fixed 

 sighting surface, the pivot being even with the edge of the sight- 

 ing surface. A suitable scale is marked along the edge of the 

 groove, and a similar scale is marked on the pendulum, beginning 

 at the pivot. The pendulum block is then moved along the groove 

 until the pivot stands at the point on the scale corresponding to 



