58 
the total number 175*5. It appears that a fall of rain, in 
excess of the average, is generally accompanied by an 
increase in the amount of oscillation. In the months of 
February, April, May, June, July, October, and December, 
a temperature below the mean for the month appears to 
increase the amount of oscillation ; whilst in the remaining 
months of January, March, August, September, and 
November, the opposite appears to hold good. A number 
of oscillations above the average appears to be accompanied 
by a greater fall of rain than that accompanying a number 
of oscillations below the average, in the months of January, 
February, March, June, October, November, and December. 
In the remaining months of April, May, July, and September, 
a number of oscillations above the average appears to be 
accompanied by a diminished fall of rain. 
If the month of June is regarded as abnormal (which is 
probable, as I have no observations for this month in 1851, 
1857, 1859, and 1860), we appear to have two distinct laws, 
one of which holds good in the winter months, and the other 
its direct converse in the summer months. Taking the 
entire year, these two laws appear very nearly to balance one 
another. 
Mr. Baxendell, F.R.A.S., read a Paper “ On the 
Irregular Oscillations of the Barometer at Lisbon.” 
In this Paper the Author gives the results derived from 
a valuable series of barometrical observations made at Lisbon 
during the twelve years 1849-60, by John Martin, M.D., 
and kindly presented by him to the Section through Mr. 
Mosley. These observations were made daily at 9h. a.m., 
the barometer being permanently fixed at about fifty feet 
above the mean level of the Tagus, and the readings uniformly 
reduced to the temperature of 32° Fahrenheit. 
From the tables which accompany the Paper it appears 
that at Lisbon the maximum amount of oscillation occurs in 
