Proving that the Earth is Round 773 



Figure 2 



In setting up this apparatus the legs of 

 the standard were driven into the gravel 

 at the water's edge, the board being over 

 the surface of the water. Plumb lines 

 were dropped from the ends of the hori- 

 zontal line, and both ends were placed at 

 the same height above the water surface 

 (in this case, four feet two and one-half 

 inches). Figure 2 is an illustration of 

 this apparatus. 



At B ( figure i ) , near a wharf which 

 extends into the lake, a bar was erected. 

 This bar (figure 3) was also mounted on 

 a chart standard. It was set up in such 

 a way that it was parallel to the hori- 

 zontal line of the first piece of apparatus. 



Figure 3 



and it was made level by dropping plumb 

 lines from the ends of the bar. The bar 

 was covered with white paper. It was 

 an inch in diameter, and its center was 

 placed four feet two and one-half inches 

 above the surface of the lake. At C a 

 telescope was mounted on a third stand- 

 ard. The telescope was a two-inch 

 glass, and it magnified about twenty-five 

 diameters. The axis of the telescope 

 was placed at four feet two and one-half 

 inches above the water surface. The 

 horizontal line of the apparatus at A, the 

 middle of the bar at B, and the axial line 

 of the telescope at the point of support 

 were at the same distance above the 



