466 
MR. BAILY ON THE CORRECTION OF 
account for a difference of upwards of two vibrations in a day which actually 
occurs in one of the pendulums above alluded to ! The following Table,, how- 
ever, will set this matter in a clearer point of view, and show the real differ- 
ences which I have found to take place in the results, merely by reversing the 
face of the pendulum. The numbers, in the first column, have reference to 
the enumeration of the pendulums in the preceding part of this paper. The 
brass bar, § of an inch thick, was swung on two different agate planes ; and 
the results by no means accord with each other. 
Differences in the results, by merely turning the face of the pendulum . 
No. 
Pendulums. 
Difference, 
1—21 
22 
25/ 
26 / 
25/ 
26 / 
27/ 
28/ 
29/ 
30/ 
3 M 
32 l 
33 f 
34 J 
French knife edge 
Kater’s invariable, No. 11 
Brass bar, •§ inch thick / ! vn ^ e ec |o e ^ 
8 / knife edge B 
Same Brass bar on other planes. . . . <f | £I1 !^ e ct ]^ e ^ 
1 /knife edge B 
Copper bar § inch thick {knife edge B 
Iron bar | inch thick { knife edge B 
f knife edge A 
Brass bar, f inch thick ^ g 
L knife edge D 
0-249 
0-914 
0-135 
0-939 
0- 725 
1 - 078 
0-296 
0-171 
0-121 
2-038 
0-707 
0-044 
0-473 
0-614 
As the experiments, here alluded to, were made for the express purpose of 
detecting any discordance arising from the position of the knife edges on the 
agate planes, they were at first followed up (as far as each pendulum is con- 
cerned,) in immediate succession; alternately turning the face of the pendu- 
dum at the end of each experiment. It is needless to swell this paper with a 
detail of the whole of the experiments that were made on these occasions ; but 
as the 10th case above enumerated (the iron bar No. 30, knife edge B,) affords 
so remarkable a discordance, I trust I may be excused for putting on record 
the steps of the process ; by means of which the results may be verified at 
pleasure. The magnitude of the discordance (like the case already mentioned 
in page 461), was the cause of its detection, which may therefore be considered 
as accidental : but the discovery of the anomaly led me to suspect that it 
