during the Quarter ending September 30, 1849. 361 



the end of the month. The range of readings during the 

 month was 0*94 inch. 



In August the reading increased to 30*02 inches on the 

 morning of the 2nd at 9 a.m. ; decreased to 29-78 on the 5th 

 at 10 A.M. ; increased to 29*95 on the 7th at 9 a.m. ; decreased 

 to 29*56 bv the 9th at 9 p.m. ; increased to 29*95 on the 7th at 

 9 a.m.; decreased to 29*56 by the 9th at 9 p.m.; increased to 

 29*79 on the 1 1th at 9 a.m. ; decreased to 29*46 by the 13th at 

 3 P.M.; increased to 29*74 by 3 p.m. on the 15th; decreased 

 to 29*54 on the 16th at 3 p.m.; it then increased and passed 

 the point 30 inches about midnight on the 18th, and was 30*22 

 on the 21st; at which reading it continued almost all the day, 

 and then decreased, slowly passing below 30 inches after noon 

 on the 25th, to 29*69 on the 30th at 9 p.m., and then in- 

 creased to 29*74 by the 31st, The range of readings in the 

 month was 0*66 inch. 



The reading decreased on September 1st to 29*50 inches at 

 9 P.M. ; then increased slowly till the 7th at midnight, when 

 it was 30*05 ; the decrease on the 8th was slow ; it was rapid 

 on the 9th and 10th; and the reading on the 11th was 29 

 inches nearly all the day ; on the 1 2th at noon the reading 

 was 28*88, being the lowest in the quarter ; after this time the 

 reading increased, and passed the point 30 inches before noon 

 on the 14th; and continued to increase till the 19th at noon, 

 when it was 30*36, being the highest in the quarter; after 

 this time it decreased, and passed below 30 inches before noon 

 on the 22nd, and continued to decrease till the 27th at 3 p.m., 

 when it was 29*61 ; it then decreased slightly to 29*73 of the 

 morning of the 28th ; and then decreased to 29*08 by the end 

 of the month. The range in the month was 1*48 inch, being 

 greater than usual. 



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

 temperature, humidity and pressure, was 524*6 grains. The 

 average for the preceding eight years was 525*8 grains. 



The rain fallen at Greenwich in July was 2*9 inches, in 

 August was 0*45, and in September was 3*3. The amount 

 for the quarter was Q>'Q. The average for this quarter in the 

 preceding eight years was 7*2. 



The fall of rain in August was less than has fallen in August 

 since the year 1819. The average fall of rain at Greenwich, 

 from thirty-three years' observations, in July is 2*5, in August 

 2*4, and in September 2*4 inches. The fall was less than its 

 average at places south of latitude 53°, exclusive of Cornwall 

 and Devonshire; it was about its average fall between 53° 

 and 54° of latitude ; and north of 54° the fall was greater 

 than usual. 



