86 
The amount of oscillation in October was not remarkable 
for its excessive amount, but for the very sudden changes 
which took place towards the end of the month, say from the 
23rd to the 31st. 
For November the reading was high until the 15th, when 
a sudden change commenced, the great depression of the 22nd 
showing the extremely low reading of 28*240 inches. The 
amount of oscillation during the first half of the month only 
amounted to about half an inch per week, leaving more than 
six inches for the amount of oscillation during the last half 
of the month, against an average of 5*851 inches for the last 
seventeen years for the entire month. 
The amount of oscillation for the two months of October 
and November for the last five years, in continuation of the 
values given in my paper in vol. i., 3rd series, of the Memoirs 
of the Society, are as follows : — 
OCTOBER. 
NOVEMBER. 
Year. 
Number 
of 
Oscillations 
Amount 
of 
Oscillation. 
Rainfall. 
Number 
of 
Oscillations 
Amount 
of 
Oscillation. 
Rainfall. 
1861 
13 
Inches. 1 
5-087 1 
Inches. 
1-230 
15 
Inches. 
7-491 
Inches. 
3-878 
1862 
18 
6-569 
5035 
13 
5-323 
1-685 
1863 
12 
4-648 ! 
6-242 
14 
7-496 
2-904 
1861 
14 
5-110 ! 
1-898 
20 
8-504 
3-255 
1865 
14 
6-361 
5-005 
15 
7'390 
2-770 
Means of 
17 Years.. 
| 155 
5-851 
13-8 
5-804 
In the paper last alluded to I pointed out at page 3 that 
an excessive amount of rainfall was accompanied also by a 
large excess of barometric oscillation in every month but 
October, stating also that perhaps a longer period of observa- 
tion might remove this apparent anomaly. The last five 
years, however, give exactly the same abnormal values for 
October, as reference to the small table annexed will show. 
October, 1863, with the least barometric oscillation, had the 
largest rainfall out of the five years. November conforms to 
