132 METEOROLOGY. 



Altarnun, 26°, the instrument on grass marking 17". The rainfall and 

 number of rainy days did not vary much from the ordinary standard for the 

 month. There was a heavy gale on the 29th, from W. by N., the velocity 

 of the wind at Falmouth reaching 59 miles an hour at 9 a.m., the barometer 

 there dropping to 28-664, the lowest point for the year. The weather towards 

 the end of the month was exempt in Cornwall from the fogs and severe cold 

 ■which prevailed up the country after the 21st. 



December was a rough and wintry month in this county, although we 

 escaped the intense frosts which characterized the season further east. The 

 quantity of rain in the western districts was almost twice the usual amount, 

 and about one-third beyond it in the eastern, and only 5 or 6 days — at Al- 

 tarnun only 3 — were quite dry. It blew hard at intervals from the 6th to 

 the 12th, and on the 8th there was a very heavy westerly gale, when the 

 highest velocity of the year, 66 miles per hour, was registered at the Fal- 

 mouth Observatory, at 11 p.m. The mean temperature of the month at 

 Bodmin was 38-9°, four degrees below the average ; but the minimtim was 

 only 30° in the stand, and 24° on the grass : this was on the 18th when it 

 was 18° on the grass on my lawn, and 26 in the shed at the Eoyal Institution. 

 This was the greatest cold of the month, and also of the year. At Falmouth 

 Observatory the lowest point was 32-40, being on the same day. At Altarnun 

 the cold was much more intense, 21° having been registered on the stand, 

 and 12 on the grass ; and " on only four nights did the temperature of vege- 

 tation not fall below 32 derees." Even at Truro frost is recorded on 12 nights. 

 A pretty correct estimate of the differences of the localities at night in this 

 month may be derived from a comparison of the mean of the minima at 

 each. This is for Scilly, 40-4° ; Penzance, 38-9° ; Helston, 36'8° ; Falmouth, 

 38-2° ; Truro, 35"5°. The warmth derived from the sea is here strongly 

 marked. This year ended and the next began with torrents of rain, and 

 little cold, whilst the utmost rigour of winter was being experienced through 

 the greater part of England. After giving details of the general mildness 

 of the quarter previously, Mr. Glaisher remarks: — "On 21st November a 

 " severe cold period set in and continued with very slight exceptions till 1st 

 " January, 1875 ; the average daily temperature of the 42 days ending on 

 " this day was 33*5°, being 6"6° below the average. The temperature on 

 " several days was more than 10° in defect, and on the last day of the year it 

 " was as large as 16|° nearly. On this day the mean temperature was 21-10 

 " only ; the day being painfully cold." The lowest temperatures were on the 

 30th and 31st, when the minima were at Cardington, 6° and 10°; and at Hull, 

 5° and 9°. It is worth notice that the minima on the same days were 27'5o 

 and 27° at Guernsey, when they were 37° and 32° at Truro. The predomi- 

 nance of a westerly element in the wind during all this period was, no doubt, 

 the main cause of the mitigation of the cold with which we were favoured. 

 The whole winter deserves further consideration, inasmuch as it exemiDlifies 

 very clearly the conditions of the varying differences between the climates of 

 the S.W. of England and that of the N. and E. at this season of the year. 



C. BABHAM. 



