of Reducing Observations of Temperature. 27 
of the values of e, bearing in mind that a degree nearly cor- 
responds to a day, and that the pani are earlier in propor- 
tion as ¢ is greater. 
As an instance of the convenience afforded by the present 
method, for comparing the climates of different countries, I 
subjoin the values of A, a, and e, for Edinburgh and Pictou, 
(Nova Scotia), the former derived from the monthly means of 
the late Mr Adie’s observations, embracing a period of 40 
years, for which I am indebted to a paper by Principal Forbes, 
as epitomised in the “‘ Edinburgh New Philosophical Journal ;” 
the latter from 11 years’ observations by Mr Henry Poole, 
manager of the Albion Mines. 
The monthly means themselves are :-— 
For Edinburgh. 
86:69 37:99 4061 44:83 50:27 55°66 58:27 57°44 
53°73 47°47 41:21 38-60. 
For Pictou. 
19-85 19:90 27-41 37-38 48:58 5814 66-10 65:19 
56-05 46-28 35:59 24-47. 
From which are derived the following values of mean tem- 
perature, amplitude, and epoch, or A, a, and e:— 
A. a. é. 
Edinburgh, . . 46:9 10°8 83° 27 
Fictous N. S.,...... 42°] 23-0 ee 1s 
Hence, cleared of technicalities, the relation between the 
_ two climates may be expressed by saying, that Pictou is on 
the average of the year about 5° colder than Edinburgh, that 
its range is rather more than double, and that its seasons are, 
on the average, 5 days later. No such definite information 
is obtained by inspecting the monthly means. 
At Isle Jesus, nine miles from Montreal, the values of A, a, 
and e are about 40:9, 29:4, and 85°56’. ‘Lhe range at this 
place is therefore nearly three times as great as at Edinburgh, 
and the phases of temperature are two or three days earlier. 
With a view to satisfy myself of the accuracy of results 
obtained by the present method, I have examined two points 
which seemed open to suspicion. _ 
I. If, in the process for finding the coefficients, we had 
