190 Mr. J. Glaisher's Remarks on the Weather 



in the month of May exceeded the average value for that 

 month by 12°*9, and it was larger than the mean daily range 

 in any month in the preceding seven years. The next largest 

 mean daily range was 22°"5, which took place in the month 

 of June 1846. The average for the quarter was 21°'6, being 

 3°*4 in excess over the average for the seven years ending 

 184-7. 



In April the readings of the thermometer on grass were at 

 or below 32° on twelve nights, and the lowest reading was 25°. 

 In May they were at or below 32° on fourteen nights, and on 

 eleven other nights the readings were below 40°. In June the 

 lowest reading was 31°*5 : on six nights the readings were be- 

 tween 32°and 40°. The amount of heat radiated at night from 

 the earth in the month of May was very great indeed. The 

 observer at Leeds says, that white frosts were almost of nightly 

 occurrence during this month. The observer at Beckington 

 speaks of the severe frost of the 30th of June, and which was 

 general over the south of England. 



The mean amount of cloud for April was 7*3, for May was 

 3'0, and for June was 7*4. The month of May presented this 

 remarkable peculiarity, — that the sky was absolutely cloudless 

 both day and night during the first eight days, and almost free 

 from cloud till the 15th day, the atmosphere being free from 

 haze during this time. These circumstances are without a 

 parallel on record. The sky during the months of April and 

 June was more clouded than usual, so that the mean amount 

 for the quarter, viz. 5*9, is only 0*2 less than the average for 

 the corresponding quarter of the seven previous years. 



There were three exhibitions of the aurora borealis during 

 the quarter, which occurred on April 3, 7, and 29. 



The electricity in the atmosphere during the month of April 

 was generally in an active state, and rather more than the 

 average amount. It was frequently negative, which circum- 

 stances always preceded or occurred during the fall of rain. 

 In the month of May the amount of electricity was small, and 

 particularly during the first half of the month, excepting on 

 the 3rd, 4th, and 5th, on which days very active positive elec- 

 tricity was shown. Till the last week in June the electricity 

 was frequently active, being mostly positive, and at times ne- 

 gative. Generally the electricity was positive at all times 

 when rain was not falling, and at times after rain had been 

 falling for some time. 



Thunder-storms at different parts of the country occurred 

 on April 1, 2, 7, 17, 19, May 10, 14, 15, 18, 20 and 26, June 

 12 and 22. The heaviest of these storms occurred on June 12, 

 and extended over all the southern parts of the country, in- 



