29 
Here the maximum occurs in the winter and the mini- 
mum in the summer quarter, the character of the changes 
thus agreeing almost exactly with that shown by the Lisbon 
observations. 
The annual values are 
1858 ... 
... 3-6 
1863 ... 
... 4-5 
1859 ... 
... 4-4 
1864 ... 
... 4-6 
1860 ... 
... 4-5 
1865 K ... 
... 5-1 
4-17 
4-73 
The mean for the three years of maximum solar spot 
frequency is 4T7, and that for the three years of minimum 
is 4 '73, the difference being 0*56, thus showing an action 
precisely similar to that shown at Hobart Town and at 
Oxford. 
Ozone observations were made at the Sydney Observatory 
during the four years 1860-63, but I have not yet been 
able to meet with the details. The annual amounts, how- 
ever, were, 
1860 
6-15 
1861 
5-20 
1862 
4-23 
1863 
4-00 
Here we have a gradual diminution of the amount of ozone 
corresponding to a gradual decrease in the frequency of 
solar spots, thus exhibiting a character similar to that 
presented by the Lisbon observations, and tending to show 
that there exists in the southern hemisphere a belt or zone 
of ozonised air similar to that which I have supposed to 
exist in the northern hemisphere, and subject to similar 
movements. 
The published “ Greenwich Observations ” afford a series 
of only three years of daily observations of ozone, and the 
results differ widely from those obtained at Oxford and 
