22 
Mean 
lOh. p.m. 
Mean 
lOh. a.m. 
Mean 
lOh. p.m. and 
lOh. a.m. 
January. ..... 
... 2-5 .. 
.... 2-8 .. 
.... 2*65 
February ... 
... 2-9 .. 
.... 3-7 . 
..... 3-30 
March ...... 
... 3-6 .. 
.... 3-9 . 
375 
April 
... 4-3 .. 
.... 4-5 . 
..... 4-40 
May 
.. 5-3 .. 
.... 5-8 . 
..... 5-55 
June 
... 4-4 .. 
.... 4-8 . 
..... 4-60 
July 
... 3-6 .. 
.... 4*1 . 
..... 3-85 
August 
... 4-0 .. 
.... 4-5 . 
..... 4-25 
September . . . 
... 3-6 .. 
..... 3*9 . 
3-75 
October 
... 2-8 .. 
.... 3*2 . 
..... 3-00 
November ... 
... 1-9 . 
..... 2-0 . 
..... 1-95 
December ... 
... 2*1 .. 
2-5 . 
..... 2-30 
The curve No. 2 in the annexed 
diagram is a projection of the 
numbers in the last column, while 
curve No. I is a projection of Mr. 
Mackereth’s results. 
It will be seen that the prin- 
cipal maximum and principal 
minimum both occur one month later at Oxford than at 
Eccles ; and that a secondary maximum occurs at both 
stations in the month of August. 
It is stated at the foot of the table in the “ Radcliffe 
Observations” that the following facts are deducible from 
the above numbers : 
1. That the greatest quantity of ozone generally occurs 
in the spring, and the least quantity in October and Novem- 
ber. • 
2. That the absolutely greatest quantity occurs in May. 
than in the morning. 
During the whole period of ten years there is only one 
