Meteorology. 75 
To Mr. Tilloch. 
Croydon, 29th Dec. 1818. 
S1r,—I beg to hand to you for insertion in your useful Ma- 
gazine the quantity of rain and evaporation at Croydon in Sur- 
rey during the year 1818; and it will be found by comparison 
with the last year’s gauge that the quantity of rain fallen this 
year is less by full one inch than what fell in 1817, the quantity 
in 1817 being 25-849 inches, and this year only 24+252 inches; 
and (what is remarkable) that although this year has been so fine, 
we had more rain by one inch and seven-tenths during the 
progress of the year to the beginning of October, than we had in 
the same period of 1817; the comparative dryness of October 
and December last past, having reduced the quantity on the whole 
year to the result above stated. 
The evaporation you will perceive has this year been greater 
than the last by nearly five inches, the evaporation in 1817 be- 
ing 22-227 inches, andin 1818, 27-064 inches. 
I remain, sir, your obedient servant, 
Henry Lawson. 
P.S. The gauges are placed four feet from the ground, as 
described in your Magazine for January 1818. 
Rain and Evaporation noted at Croydon during the Year 1818. 
j Evapo- Evapo- 
Month. Rain. |ration. Month Rain. ration, 
From 1818. 
28 Dec. 1817, 12 to 19 July,| 0-023} 1-132 
to 4 Jan. 1818, 0-126 | 0-015 19 to 26 0-170 | 1:444 
4to il 1-092 | O'145 26 to 2 Aug,| 0.218] 0-958 
11 to 26 0-615 | 0-320 2 to. 9 0-001} 1-354 
26 to 1 Feb. | 1-101 | 0-242 9 to 16 0-000 | 1-087 
lto 8 0-056 | 0-069 16 to 23 0-003 | 0-754 
8 to 15 0-010 | 0-049 23 to 30 0-089 | 9-801 
15 to 22 0-719 | 0-150 30 to 6 Sept.| 1-209 | 0-973 
26 to 1 Mar.| 1-088 | 0-295 6 to 13 0.103 | 0-563 
1 to 8 2-265 | 0-516 13 to 20 0-268 | 0-556 
8 to 15 0-391 | 0-309 20 to 27 1-997 | 0.401 
15 to 22 0-219 | 0-423 27 to 4 Oct.} 0-940] 0-373 
22 to 29 1.090 | 0-419 4 to ll 0°365 | 0-291 
29 to 5 April] 0-015 | 0-468 11 to 18 0-255 | 0-325 
5 to 12 1-169 | 0*367 18 to 25 0-071 | 0-238 
12 to 19 0-053 | 0-573 25 to 1 Nov. 0-231 | 0-172 
19 to 26 1-059 | 0-421 lto 8 0-113 | 0-140 
25 to 3 May.| 1-049 | 0-664 8 to 15 (925 | 0-140 
3 to 10 1-507 | 0-721 15 to 22 0'374| 0-101 
10 to 17 0-309 | 0-575 22 to 29 0:478 | 0-054 
17 to 24 0-030 | 0'835 29 to 6 Dec.} 0-206] 0-065 
24 to Sl 0-003 | 0-889 6 to 13 1-072} 0-022 
31 to 7 June,| 0-000 | 1-299 13 to 20 0187} G-012 
7 to 14 0-025 {| 17135 20 to 27 0-018 | 0-071 
14 to 21 0,274 | 0-818 |} —————-——_—_- 
21 to 28 0-359 | 1-079 || ‘Total in the year |24-252 |27:064 
28 to 5 July,| 0-013 | 1-182 
to 0-301 
