1 84 Mr. J. Glaislier's Remarks on the Weather 



For the month of December was 4-2°*3, which is 3'^*5 above 

 that for the preceding seven years. 



The mean value lor the quarter was 44'°'4', whicii is l"vl 

 above that for the preceding seven years. 



The mean temperature of' the dew-point at Greenwich — 



For the month of October was 47°'4-, which is 2^-3, 5°-0, 

 2°-7, 1°'4, 0°-9, and 0°-2 above those of the years 1841 to 1846 

 respectively, and l""*? below that of the year 1847; or it is 1^-6 

 above the average of tliese seven years ; 



For the month of November was 38°'8, which is 1°*0, 1^*6, 

 2--1, S""-!, 4'''0, 4°-3, and 5°-3 below those of the years 1841 

 to 1 847 ; or it is 3°'0 below the average for these seven years ; 



For the month of December was 40°- 1, which is 4°*9, 10°'l, 

 2^-4, 10°-7, and 0°-3 above those of the years 1841, 1844, 

 1845, 1846, and 1847 respectively, 3°'l and l°-9 beloxo those 

 of the years 1842 and 1843 ; or it is 3°'3 above the average of 

 these seven years. 



The mean value for the quarter was 42°'l, which is 0°*7 

 above the average for the corresponding period of the preceding 

 seven years. 



The mean weight of water in a cubic foot of air for the 

 quarter was 3*3 grains, which is O'l grain greater than the 

 average of the preceding seven years. 



The additional weight of water required to saturate a cubic 

 foot of air was 0*54 grain. This value from the preceding seven 

 years was 0*38 grain. 



The mean degree of hurnidity o^ i\\e atmosphere for October 

 was 0*853, for November was 0*848, and for December was 

 0*873. The averages for the seven preceding years were 0*888, 

 0*909, and 0*900 respectively. The value for the quarter was 

 0*858, which is 0*041 less than the average for these years. 



The mean elastic force of vapour for the quarter was 0*285 

 inch, which is 0*008 less than the average for the preceding 

 seven years. 



The mean reading of the barometer at Greenwich for October 

 was 29*646 inches, for November was 29*785 inches, and for 

 December was 29807 inches; these values are 0*014 inch 

 below, 0*075 inch above, and 0*028 inch below the average for 

 the same months from the preceding seven years. The mean 

 value for the quarter was 29*746 inches, which is 0*011 above 

 the average for these years. 



The average weight of a cubic foot of air under the average 

 temperature, humidity, and pressure, was 540*3 grains; the 

 average for the seven preceding years was 542 grains. 



The rain fallen at Greenwich in October was 3*50 inches ; 

 in November was 1*20 inch; and in December was 2*55 inches. 

 In October, in the years 1841 to 1847, were 5*95, 1*41, 4*25, 



