Calendar of Nature. 567 
The double lines, marked 4, show the motion of the mercury in the ba- 
rometer ; ¢s w, the mean temperature of the air near a south garden-wall ; 
t, the mean temperature in the open air and in the shade; d, the dew-point 
and min. t, the minimum temperature in the open air at night. 
The coldest day in August was on the 26th: mean temperature of that 
day 48°5°; extreme cold 39° three feet above the surface, and 31° on the 
grass; wind westerly. The warmest day in August was on the 4th: mean 
temperature of that day 60°5° ; extreme heat 69°; wind westerly. The mean 
temperature for the month was 54°4°, nearly 4° below the average tempera- 
ture for that month for the seven preceding years. There were 6 days of 
brilliant, and 12 of partial, sunshine ; 13 days were cloudy. The wind blew 
from easterly points on 9 days, and from westerly points on 22 days. There 
were no remarkably loud winds during the month; but on the 8th, about 
5 o’clock in the afternoon, there was a loud and violent thunder-storm, ac- 
companied with hail ; and at Errol, in the centre of the Carse of Gowrie, ice 
fell in large pieces of the size of a cubic inch and upwards, covering an area 
of about 500 acres, on which the corn crops were completely denuded of 
the partially filled grain, and the green crops of their foliage. The minimum 
temperature during the night was 46°, and yet much of the ice lay undis- 
solved in ditches and shady places till near noon the following day: a 
phenomenon of this nature is seldom observed in Scotland. The coldest 
day in September was on the 23d: mean temperature of that day 49°; 
extreme cold 41°; wind variable. The warmest day was on the 27th ; mean 
temperature of that day 58°; extreme heat 60°; wind S.W. There were 
8 days of brilliant, and 8 days of partial, sunshine; 14 days were cloudy : 
the wind blew from easterly points on 5 days, and from westerly points on 
25days. There were loud gales on the 11th, 19th, 20th, 24th, and 25th. 
The mean temperature for September was 52°9°; the ordinary temperature 
for that month is 54°7°. The fall of rain during the two past months has 
been excessive, amounting to 10°39 in. ; and from the moist state of the atmo- 
sphere, which will be observed by the line representing the dew point being 
so near the mean temperature, little evaporation could take place: conse- 
quently the soil has been all along exceedingly moist. This, accompanied with 
a temperature under the ordinary mean, has protracted the ripening process 
to a later period in the season than usual. The general clouded state of 
the atmosphere, too, has retarded the ripening of wall-fruits; for it is sun- 
shine that communicates that heat to walls by which fruit is ripened in the 
same space of time with those of the same kind some 6° or 7° farther south 
in the open air. Too much stress is sometimes laid on walls giving out 
much caloric throughout the night, by writers on gardening. On a cloudy 
day, or at midnight, a thermometer, within 6 in. of a south brick wall, will 
not indicate above a half degree higher than one on a north aspect. During 
clear sunshine, the difference in favour of the south wall is from 10° to 12°; 
but they uniformly approximate a short time after sunset: taking, there- 
fore, the mean of the daily extremes of the temperature of a south wall in 
September, when the atmosphere was for the most part cloudy, it did not 
exceed the common mean much above 2°. In August, the difference in 
favour of a south wall is as 4°2°. 
In the flower-border, the Lilium c4ndidum opened its elegant flowers on 
the Ist of August; Timothy grass in fields came in flower on the 2d; the 
Digitalis ferruginea on the 5th, four days later than last year ; Coreépsis 
verticillata on the 15th, five days later than last season. Peas that came 
in flower in the field by the 12th of July, were ripe by the 8th of Septem- 
ber, a period of 58 days: mean temperature of that period 566°; depth of 
rain73in. The excess of moisture in the air and in the soil prevented the 
pods from filling, and also retarded the ripening process. Barley that came 
in the ear on the 16th of July was ripe on the 10th of September, a period 
of 56 days ; mean temperature of that period 56°6° : a curious coincidence 
