326 



Ozone. 



but when the difference between the two therometers is consider- 

 able, no ozone is appreciable by the ozoneometer. This fact and 

 the only one which (as far as my observations here go) is in con- 

 nexion with the presence or absence of ozone, has led me to com- 

 pare the presence of ozone with the presence of precipitation in 

 the shape of snow or rain, which gives a remarkable co-incidence. 

 For in and during the past seven years there were 918 days on 

 which rain or snow fell, (this is regardless of the amount or dur- 

 ation,) and during the like period there were 816 days on which 

 ozone was present in a quantity of five-tenths, any amount below 

 that quantity in this estimation is not taken into consideration in 

 the discussion. In the year 



1850 there were 106 days of precipitation, and 110 days of ozone. 



135 

 152 

 114 

 T3 

 110 

 126 



The small amount of ozone in 1854, which was the year of the 

 last visitation of cholera, would tend to favour the opinion that 

 there was a deficiency of ozone in the atmosphere during the 

 prevalence of that epidemic. A deficiency was, however, observed 

 in almost every month of that year, although the number of days 

 on which snow or rain fell were almost equal with the other years, 

 which see the following table, which shews the amount for each 

 year, and for each respective month : — 



1851 





123 



1852 





136 



1853 





136 



1854 





133 



1855 





140 



1856 





144 



YEARS. 



1851. 



1852. 



1853. 



1854. 



1855. 



1856. 



Months. 



DATS 



u 



01' 



O 



o 



P 



CD 



5 



V 



6 



8 



14 



12 



16 



15 



15 



11 



13 



13 



135 



DATS 



• ?■ 



OF 



O 

 o 



DATS 



OF 



O 



i 



a> 



DATS 



OF 



O 



o 

 5 



DATS 



OF 



o 



i 



DATS 



.if 



OF 



O 

 o 

 » 



January, .. 



10 

 6 

 11 

 12 

 16 

 12 

 13 

 8 

 11 

 12 

 10 

 11 



14 

 11 

 17 

 10 



9 

 17 

 11 



9 

 10 

 17 

 10 

 18 



7 

 8 



11 

 11 

 8 

 18 

 17 

 16 

 16 

 18 

 12 

 14 



9 

 11 



9 



7 

 16 

 15 



9 

 13 

 11 

 14 

 U 



8 



11 



9 



21 



12 



12 



11 



4 



7 



9 



5 



11 



8 



14 



16 



17 



10 



8 



10 



5 



7 



11 

 11 

 13 

 12 



6 

 6 



7 

 6 

 7 

 8 

 4 

 3 

 3 

 8 

 11 

 7 



12 

 8 

 9 

 14 

 6 

 15 

 7 



11 

 12 

 18 

 14 

 14 



6 



9 



6 



8 



9 



12 



11 



12 



11 



11 



9 



6 



12 

 9 

 10. 

 11 

 13 

 10 

 12 

 15 

 14 

 10 

 15 

 11 



14 



February, 



March, 



16 

 17 



April, 



20 



May, 



20 



June, 



17 



July, 



18 



August 



11 



September 



October, 



12 



8 



November, 



December 



8 

 5 



Total. 



123 



136 



152 



136 



110 



133 



73 



! 140 



110 



144 



126 



