servations kept at different places indicate a temperature somewhat
higher than the true mean of the place. For they are generally kept
only during the day; and the night when the thermometer is lowest of
all is entirely neglected. Two observations made every 2 4 hours
would be sufficient to give us the true mean, if one of them were
made when the thermometer stands highest, or about two in the afternoon,
the other when the thermometer stands lowest, which is believed
at present to be just before sun-rise. But I am not acquainted
with any table o f observations kept upon this principle. Those who
are furnished with a Six’s thermometer may easily obtain the true
mean by noting down the greatest cold in the night, and the
height of the thermometer at two o’clock in the afternoon for a whole
year.
From the observations kept at Enontekis, we learn, that during
summer and autumn the temperature of the air is warmer at noon than
in the morning, just as happens in milder climates-. But during
winter the very contrary takes place, the temperature of the air at noon
is always lower than in the morning. Indeed we have no reason to
expect that in that climate the temperature should be regulated by
the time o f the day. For as the sun does not appear above the
horizon, it can produce no effect upon the temperature. The following
table drawn up by Dr. Wahlenberg, from the register o f observations
kept at Enontekis, will serve to exhibit the variation of temperature
in that place during the year.
Mean from the highest Mean from the lowest Mean from Mean of the
.observations. observations. both. months.
o 0 0
January 1 to 10 . ........ 2*62 . . . . .. — 7*24 .........., —2*29
11 — 20 . ........ 5*54 .. — 3*64 .......... 0.95 0
21 — 31 . •6*44-.... .. — 1*30 .......... • 2*57 ........ 0*41
Feb/ 1 — 10 , ------—3*82 ____ — 11*02 .........., — 7*42
11 — 20 . ........ 8-24 ___ .. — 3*82 ......... 2*21
<0n0
1
CM
. . . . . 7*34 . . . . 3*56 ........ . — .0*55
Mean from the highest Mean from the lowest Mean from Mean o f the
observations. observations. both. months.
March 1 to 10 . 4*28 ........... 10*18
11 -r— 20 . 4-46 .......... 11-75 o
6*08 ........... 12*29 ___ 11-41
April 1 10 ..,.•.-.. 29-84 -------... - 18-14 . . . . . . 24-04-
11 — 20 . R 21.92 ........... . 26-33
"1 30 24*98 ........... 27*68 . . . . 26*02
May 1 10 . . . . . . 36*14 . . . . . 28*22 •.. .. * 32*18
11 — 20 i ........ 40*64 ......... 33*62 .......... 37*13
21 — 31 | ____ 43*52 ......... 37*22 .. .. • • 40*37
June 1 — 10 . H R 46*76 . . . . . 1 39?92 43-34
11 — 20 1 49*10 .......... 53-33
48*56 ........... 51*80 ___
July 1 10 ... . . . . . : 62.24 . 53*96 . . . . . . 58-10
11 20 .......... 64-22........... . , 55-76 ........... 59-99
56*84 ........... 60*80
August 1 — 10 . ......... 64*94 . . . . . 58-10 ........... 61*52 :
11— 20 . ........ 61-52 . . . . . 52-52 ........... 56-52
21 — 31 ........ 52-70 ......... 46*58 . . . . . . 49*64 \ . ..
Sept. 1 — 10 1 ........ 47*66 ......... 38-84 . . . . . . 43*25
11 — 20 1 . . . .. 49*10 ........ 39*92 ........... 44*52
21— 30 ........ 40-82 34*34 . . . . . . 37*58 . . . .
Oct. 1 — 10 ........ 33-98 ......... 26*06 ___ 30-02
11 — 20 . 26-60 ........... 30-47
21 — 31 . 27*32 . . . . . 16*34 ........... 21-83 27*44
Nov. ' 1 — 10 . . . . . . 21-74 . . . . . 14-18 ........... 17*96
11— 20 . ........ 19-63 ......... 11-50 ........... 1-5-56
21— 30 1........ 7*36 ......... . — 1-00 ............... 3-18 12-20
Dec.. 1 — 10 _____ 6-98 — 1-12
11— 20 .......... '8-06 — 4-54
21 — 31 ........... 3*56 ............— 6-88.
Mean ____ 81r26 22'44
Winter (months i. ii, and xii.) mean from the highest observations.................. 5°*04'
Ditto from the lowest ............’ . V . ........................... — 4 *38,
Difference . . . . . . f ; . . . i . . . . . . . . . . . . . . . . . ............................................ 9 "42:
2 T
2-93
1-76
— 1:66 1-01
26-85