154 Messrs Coldstream and Foggos Meteorological 
4. Rain, 2.6 inches in 20 days. 
5. Winds, N. 2, E. 1, S. 4, SW. 7, W. 11, NW. 6 days. 
Remarks. 
This month has been characterised by the prevalence of strong westerly 
gales, accompanied during the first two weeks by heavy rains, and, towards 
the latter end, by frosts. 
7 th — Much rain fell to-day. Mean pressure 29,605. Mean temp. 54°.5. 
Dew-point 54°.0. An aurora was seen in the evening : observed synchronous- 
ly in the north of Scotland. 
17$ — Solar Radiation at 9 a. m. 95°. Mean temperature 49°.5. Dew- 
point 36°.5. Weather variable, showery. 
1 8th — Temperature of the preceding night 37°. 
21s£. — The hygrometrical observations of the last four days have illus- 
trated very well the beautiful law, first developed by Mr Anderson of Perth, 
of the coincidence between the dew-point and the minimum temperature of 
the night. The following is an abstract of these * : 
1825. 
Temperature. 
Weather. 
Min. 
Max. 
Ther. 
Dew-p. 
DifF. 
October 17- 
46°. 0 
55°.0 
49°.0 
36°.5 
12°. 5 
Variable; showery. 
18. 
37.0 
55.0 
47.0 
44.0 
3.0 
Dull; fine. 
19. 
43.4 
49.0 
44.0 
37.0 
7-0 
Clear : then rain. 
20. 
21. 
36.0 
35.0 
42.5 
40.0 
35*0 
5.0 
Clear; very fine. 
Ditto, ditto. 
28th A lunar halo, with a diameter of 90°, was seen to-night formed in 
cumulated cirro-strati. Pressure diminishing. 
30$.— Boisterous gale from NW. Maximum temperature 60°. 
NOVEMBER. 
1. Temperature. 
Mean of the Month, 
Maximum by Register Thermometer, 
Minimum by ditto, 
Range, 
Mean of the extremes, 
2. Pressure. 
Mean of the month, , 
Maximum observed,, 
Minimum observed v 
Range, 
Eahr. Then 
56.500 
25.000 
31.500 
40.500 
Inches. 
30.120 
28.670 
1.450 
a Since we commenced our observations with Mr Jones’s hygrometer, it 
has often occurred to us, that horticulturists might use such an instrument 
with great advantage in this variable climate. It is now well established, that 
the temperature of the dew-point, as observed in the afternoon in any season, 
is very nearly the same with the minimum temperature of the succeeding 
night ; and hence, by making use of Mr Jones’s instrument, a frost might be 
announced in sufficient time to admit of the necessary precautions being taken 
to secure the safety of tender plants, &c. We are well assured that no gar- 
dener would find any difficulty in using the instrument. 
