426 
MR. BAILY ON THE CORRECTION OF 
The whole of the experiments with the preceding- 20 pendulums were made 
for the purpose of determining- the additional correction due to bodies sus¬ 
pended by a fine wire, or by a very thin rod: this being- one of the forms in 
which pendulums are constructed for the purposes of physical inquiry. In 
the present experiments, the pendulums were all nearly of the same length, or 
about 39 inches; and the results tend to show that the value of n, in pen¬ 
dulums of equal length and of similar construction, depends entirely on the 
external form and magnitude of the pendulum, and is uninfluenced by its 
weight or specific gravity. But, whether any portion of this result (and, if any, 
how much of it,) is to be attributed to the wire or suspending rod ; or whether 
it is caused wholly by the sphere or cylinder; or whether the effect would be 
greater or less with longer or shorter pendulums ; or in what ratio they would 
be affected by such alterations,—must be left to be determined by future expe¬ 
riments, undertaken with a view to such special investigations *. 
I come now to pendulums of a totally different construction. 
Sixth set .—Results with the Copper Cylindrical Rod 0'41 inch in diameter, and 
5 8*8 inches long. 
No. 21. 
Exp. 
n 
109—110 
111—112 
Mean = 
2-952 
2-913 
2-932 
The factor arising from this pendulum is the greatest of any I have yet 
found: it exceeds all the preceding ones deduced from spheres and cylinders 
suspended by wires or fine rods ; and also the massy bar pendulum No. 31—34, 
which is 2 inches wide, § of an inch thick, and 62 inches long. 
* Since this paper was read before the Society, I have made several experiments to determine some 
of the points here alluded to; which, by permission of the Council, are added to this paper, and will 
be given in the sequel. They tend to open a new view of the subject; inasmuch as they show that, 
in pendulums suspended in the manner mentioned in the text, the value of the factor n is affected not 
only by the magnitude of the sphere or cylinder, but also by the magnitude and length of the rod or 
wire. 
