_Astronomy. 141 
voidable errors of observation, to imperfection in the apparatus used, 
and possibly to ordinary causes of disturbance. The second, third, 
and fourth results, which appear to be regularly diminishing, were ob- 
tained in close succession, the instant of ending the first 100 oscillations 
being the beginning of the second 100, and the end of the second | 
being the beginning of the third 100, as will be seen by the differences 
of the times, being 17 minutes. Their diminution is due to the grad- 
ually diminishing are of vibration, the initial arc being somewhat large 
—8 or 10 degrees—in order to allow of 300 continuous vibrations. 
more delicate suspension would have been desirable. The initial arc 
in the other cases was about 5 degrees, and the observations continued 
© 200 oscillations, except in the first and fifth results. We may from 
these fesulis draw the conclusion that there were no disturbances of 
the magnetic intensity due to the occurrence of the eclipse, although 
the strictly logical deduction is, that if such disturbances existed, they 
he m 
Sth—8 09, a.m. : : 17 17-0 
7 00, P. M. xs * 17 16.88 
6th—8 08, a. M. - - 17 18°45 
8 25,“ . 2 1S: 
LE 47,4 : General eclipse begins. 
12 05, Pp. mu : . 17 16:88 
12 22, «+ : : 17 17-23 
238, “ - General eclipse, middle. 
2.00, ‘ 17 18-02 
4 00, “ Z 
5 4y,, : General eclipse ends. 
635, “ i ‘ 17 18-83 
10 00, « - 17 18 66 
8th—8 00, a ‘ * 17 17:82 
10 00, * ‘ ‘ 17 17:26 
? 
These results show no disturbance proceeding from the occurrence 
of the Solar Eclipse, and we cannot avoid the conclusion that the Pro- 
ach result in the above tables is the mean of five sets taken in the 
mode usually adopted in such observations, except the first in the first 
table, which is a mean of three. More, therefore, than 5000 oscilla- 
Hons, or more than 10,000 vibrations have contributed the results in the 
first table, and more than 12,000 vibrations the results of the second 
of Charleston, Ist June, 1854. 
