jMr. T. G. Bunt's Pendulum Experiments. 



273 



continued action of the wire. This centre appears to be better, 

 and to produce less elHpticity of motion than any other that I 

 have tried. As a specimen of its performance, I copy from my 

 minutes the concluding experiments of this series, which are as 

 follows : — 



Thus vibrating lO'' 19"" without more than ^y-d of an inch ellip- 

 ticity, its mean hourly motion in azimuth being 13°09. 



The following is a summary of the whole series of experiments 

 collected into two groups, according to the direction of the elliptic 

 motion. When the sign of h is positive, the motion is fi-om N. 

 to E. ; when negative, from N. to W. 



The mean hourly motions for every 20° of the azimuth are as 

 follows : — 



My second pendulum was 8 feet 10 inches long, with a ball 

 of lead weighing 35 lbs., and somewhat differently suspended. 

 The wire was fixed in a hole drilled through a bar of iron, which 

 was screwed to the floor. A saw-curf was carried from one end 

 of the bar, through the centre of the hole, and a little beyond 

 it ; and the two portions of the bar firmly pressed against the 

 wire by a vice. It answered its purpose very well, and produced 

 but little elHpticity. 



Phil. May. S. 4. Vol. 4. No. 35. Oct. 1852. T 



