264 Abstracts of the Makerstoun Observations, 1843. 
If we apply a correction to the monthly means, Table I., for the Sunday means awanting, which mav be 
derived with sufficient accuracy from a comparison of the monthly means from the self-registering thermometers, 
when the Sundays are included and omitted, we obtain the true means for 1843 as follow : — 
Jan. Feb. March. April. May. June. July. August. Sept. Oct. Nov. Dec. 
38°-4 33°-0 39°-3 44°-9 46°-7 51°-8 56°-8 57°-2 55°-7 42°-8 39°-4 45°-4 
Winter, 39°-0 ; Spring, 43°-6 ; Summer, 55°-3 ; Autumn, 46°-0. 
Mean Temperature for the year 1843 = 46°' 05. 
It is evident that, for the year 1843, the months of January, February, and March constitute the meteoro- 
logical season, Winter ; and July, August, and September constitute Summer. The means for this mode of 
grouping are — 
Jan., Feb., March, 36°-9 ; April, May, June, 47°"8 ; July, August, Sept., 56°-6 ; Oct., Nov., Dec, 42°-5. 
TABLE III. — Mean Temperature of the Air at the Observation Hours for each Month and 
Quarter of 1843. 
Period. 
18\ 
20 
22\ 
0 h . 
2 b . 
4K 
6>>. 
8 h . 
10 L . 
Mean. 
j Range. 
o 
O 
o 
o 
0 
o 
O 
O 
o 
o 
O 
January 
38-10 
37 
81 
38 
07 
39 
80 
40-60 
40-05 
39-30 
38-54 
38-07 
38-72 
2-79 
February 
31-85 
31 
99 
32 
66 
34 
94 
35-74 
35-20 
33-35 
32-18 
32-05 
32-98 
3-89 
March 
34-84 
35 
85 
39 
22 
43 
07 
44-76 
44-64 
42-08 
38-84 
37-91 
39-07 
9-92 
April 
39-26 
42 
70 
47 
32 
49 
47 
50-76 
50-17 
47-44 
44-15 
42-40 
44-55 
11-50 
May 
42-10 
45 
18 
48 
45 
50 
62 
51-47 
50-98 
49-80 
47-13 
44-47 
46-57 
9-37 
June 
48-35 
51 
00 
53 
41 
55 
05 
55-92 
56-25 
55-47 
52-99 
49-24 
51-97 
7-90 
July 
5213 
56 
33 
59 
73 
61 
28 
62-41 
61-30 
59-66 
56-67 
54-10 
56-83 
10-28 
August 
September 
50-10 
54 
26 
59 
46 
63 
13 
64-91 
64-76 
62-25 
57-92 
55-25 
| 57-29 
14-81 
47-80 
50 
96 
56 
56 
61 
77 
64-24 
64- 10 
60-80 
55-50 
52-63 
55-22 
16-44 
October 
39-12 
39 
88 
43 
60 
47 
01 
47-77 
47-07 
43-32 
40-95 
40-17 
42-27 
8-65 
November 
38-22 
38 
68 
39 
93 
42 
30 
43-33 
42-03 
39-15 
38-49 
38-24 
39-59 
5-11 
December 
44-40 
44 
44 
45 
98 
46 
85 
47-35 
46-28 
45-07 
44-77 
44-59 
45-26 
2-95 
Spring 
38-73 
41 
24 
45 
00 
47 
72 
4900 
48-60 
46-44 
43-37 
41-59 
43-40 
10-27 
Summer 
50-19 
53 
86 
57 
53 
59 
82 
61-08 
60-77 
59-13 
55-86 
52-86 
55-36 
10-89 
Autumn 
41-71 
43 
17 
46 
70 
50 
36 
51-78 
51-07 
47-76 
44-98 
43-68 
45-69 
10-07 
Winter 
38-12 
38 
08 
38 
90 
40 
53 
41-23 
40-51 
39-24 
38-50 
38-24 
38-99 
3-15 
The Year 
42-19 
44 
09 
47 
03 
49 
61 
50-77 
50-24 
48-14 
45-68 
4409 
45-86 
8-58 
In obtaining the means for the month of January, the observations in the first week were rejected ; no 
observation having been made at 18' 1 in the second week, a correction was applied to the mean for that hour 
of — 3°-29, obtained from Table I. as follows : — 
{Mean temp., Jan. 9—31 = 40°-32 minus, mean temp., Jan. 16 — 31 = 43°-81} = - 3°-29. 
The means were afterwards corrected by — 0°-9, in order to render the mean for the month similar- to that 
obtained, Table I., from the whole month. 
Diurnal Variation of Temperature. — The period of minimum temperature is not indicated by the above 
observations. The maximum temperature occurs nearly at the following periods in the means for the four 
meteorological seasons : — 
Spring, maximum temperature, occurs at l h 30 m p.m. Makerstoun mean time. 
Summer, l h 45 m 
* Autumn l h 35 m 
Winter, l h 10 m ... 
The Year, l h 30 m 
If we examine the monthly means separately, it will be found that the maximum occurs about the same 
time, namely, l h 10 m in the months of January, February, May, July, October. November, and December, 
