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ANALYSIS OF THE OBSERVATORY RECORDS FOR JULY, 18C5 

 IN CONJUNCTION WITH THOSE OF BIRTHS, DEATHS, &0. 

 By E. Swarbreok Hall. 



No July of the previous eight years was so favorable to health and life, as 

 the present month, for though 1862 had the same number of deaths, 36 ; yet 

 both the " diseases causing death" and the "ages of the deceased" prove that 

 July 1865 v^s the most auspicious. The weather generally, too, was most 

 agreeable, and many days were more like temperate summer ones, than such 

 as might be expected in this mid-winter month. 



Atmospheric pressure mean was 29 '947, beiog only + '089 above the twenty 

 years' average for July. The maximnra 30-382, occurred on the 21st, and the 

 minimum, 29 '546, was recorded on the 2oth, being a range of only *836. as the 

 extreme for the month, though happening within five days. The extreme range 

 in 1864 was much more, though a much great number of days intervened 

 between the highest and lowest records. The greatest movement of the 

 barometer on any day was noted on the 8th, being a fall of — '494 of an 

 inch. Two men at the Invalid Asylum, aged respectively 72 and 71, 

 succumbed to it. On only seven other days of the month did the perturba- 

 tions exceed one-fifth of an inch. The highest rise + '422 of an inch on the 

 2'6th, followed by a rise of + 135 on the following day, caused 4 deaths on the 

 latter day. 



Wind force total was 54*13 lbs., which is -H6'40 lbs. more than the July 

 average of the previous 8 years, and was only exceeded by 1863. Neverthelesa 

 the number of calms registered was very high, exceeding the eight years' mean by 

 more than 18. The very fatal July of 1860, however, had two more. East, 

 South, South- West, West, North -West, were all above the average in frequency ; 

 while North, South-East, South, South- West, and West were above the mean in 

 force, but particularly the latter. It must, however, be noted that it was the 

 storm on the 30th, which prevailed from this quarter, that alone gave the high 

 amount to this point. 



Temperature mean, 47 "09, and •\- 1*27 more than the 20 years' average, 

 though more than two degrees colder than July, 1864, was. The self -registering 

 maxima and minima thermometers gave a mean of 49 "15 degrees, which is but 

 •67 of a degree less than what the same instruments gave in July, 1864. The 

 extremes of temperature this month, however, were greater than was ever 

 before recorded in July. The maximum, 70 on the 5th, the minimum 30 on the 

 10th. Last year they were 63 and 34 respectively. 1857 and 1863 had both the 

 maximum of 70, but 34 and 32 were their respective minima. The mean of all 

 the maxima of the present month, 58*55, exceeded 1864 by a scarcely appre- 

 ciable amount ; but the mean of all the minima, 39 "75, was less by nearly 

 one and a half degrees ; so that while the days were nearly equally warm 

 on the whole, the nights of the present month were very much colder. 



Daily range of temperature mean, 18 '81 degrees, is + 3 '46 more than the 

 20 years' average, and + 1*49 higher than 1864 had. The greatest range waa 

 26 deg., recorded on the 6th and 21st, and the lowest was 5 deg. on the 12th 

 July, 1864, had the same extremes, though the mean was so much less. 



Solar intensity had a mean of 77 degrees,being + 1'65 higher than the average 

 of the previous nine years, though nearly three quarters of a degree less than 

 1864 was. The greatest heat recorded was 92 degrees on the 5th, and the 

 smallest was, 50 on the 12th. 1864 had the same maximum, but a minimum 4 

 degrees higher. 



Terrestrial-radiation mean was, 36.76 degrees which is -fl .34 more than 

 that of the previous 9 years, though —59 less than that of July 1864. The 

 maximum was, 46.5 on the 5th, the minimum was, 27 on the 10th. The 

 latter was 3 degrees less than the minimum of July 1864. On the morning of 

 the 10th, there was ice on all still-water in the open air and even within doors 

 at the outskirts of the city. Several other mornings exhibited a copious 

 deposit of hoar-frost, but very transient in duration. 



Rain fell to the aggregate amount of, 1.60 inches being — "13 less than the 

 20 years' average for July, and — 2.84 inches less, than fell in July last year ; 

 though in both months there were the same number of wet days, i.e. 12. This 



