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XIV. Remarks on the Weather during the Quarter ending 

 June 30, 1850. By James Glaisher, Esq., F.R.S., Hon. 

 Sec. of the British Meteorological Society, fyc* 



HPHE weather during the past quarter has been variable^ 

 -*- and at times very unusual. The temperature of the 

 air till April 21 was 4°*3 above the average, and this period 

 was free from frosts. From April 22 to May 16, there was 

 an average deficiency of 5° of daily temperature ; from May 1 7 

 to June 9, the temperature was about its average value ; it was 

 8° in excess on June 11, and 13° in defect on the 15th ; and 

 during the following night the temperature of the air in many 

 places was below 32°, a very unusual circumstance for the 

 season. From June 18 to the 26th, the period was warm ; the 

 mean excess of temperature was 6°, Snow has fallen on 

 several days during the past quarter. 



The mean temperature of the air at Greenwich for the three 

 months ending May, constituting the three spring months, was 

 46°*6, being of almost the same value as that of the average 

 from the seventy-nine preceding springs. 



For the month of April was 48° # 5, exceeding that of the ave- 

 rage of the preceding seventy-nine years by 2°'8, and exceeding 

 that of the preceding nine years by l o, 0. 



For the month of May was 51°*3, being l°-3 less than the 

 average of the preceding seventy-nine years, and 3°*1 less than 

 that of the preceding nine years. 



For the month of June was 60 o, 8, exceeding that of the 

 average of the preceding seventy-nine years by 2°*8, and ex- 

 ceeding that of the preceding nine years by 1°*2. 



The mean for the quarter was 53 Q, 4, exceeding that of the 

 average of seventy-nine years by 1°'4, and being less than that 

 of the preceding nine years by o, 3. 

 'The mean temperature of evaporation at Greenwich — 



For the month of April was 45°*4 ; for May was 47°'5; 

 and for June was 54°-8. These values are 1 0, 7 greater, 3 o, 

 less, and o, l greater than those of the averages of the same 

 months in the preceding nine years. 



The mean temper attire of the dew-point at Greenwich — 



For the months of April, May and June, were 41°*7, 43°*4, 

 and 50 o, l respectively. These values are 1°0 greater, 4 o, 

 less, and l° s 8 less respectively than the averages of the same 

 months in the preceding nine years. 



The mean elastic force of vapour at Greenwich for the quarter 

 was 0*318 inch, being less than the average from the preceding 

 nine years by 0*031 inch, 



* Communicated by the Author. 



Phil. Mag. S. 3. Vol. 37. No. 248. August 1850. K 



