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ANALYSIS OF THE OBSERVATORY RECORDS FOR SEPTEMBER, 

 lim, IN CONJUNCTION WITH THOSE OF BIRTHS, DEATHS, 

 ks. By E. Swabbreck Hall. 



So mild and equable a month for the vernal equinox, as the present Sep- 

 tember lias proved, is of rare occurrence. It has been so propitious to health 

 and life, that the mortuary records are very considerably below the average 

 number of the previous seveu years' Septembers. 



Atmospheric pressure mean, 29*859, is + '081 above the twenty years 

 standard average, but much higher than either September 1863 or 1862 had. 

 The maximum, 30'373, was noted on the first day of the month ; the mini- 

 mum, 29*172, was recorded on the 15th. The extreme range of the month, 

 therefore, was 1*201 inches. September 1863 had a higher maximum aud mini- 

 mum, and a slightly more extensive range. The gi-eatest movement of the 

 barometer from 1 p.m. to 1 p.m., of any twenty-four hours in the month, 

 was a rise of + *484 on the 30th, but one of + *483 occurred on the,16th. A 

 fall of —-488 was noted on the 10th, and one of -f -407 on the 26th. Pertur- 

 bations of one-fifth of an inch to "400, were recorded seven times. 



The total force of all the winds of the month was 43*16 lbs., A\hich is 

 only slightly more than one-third of that of last years' September. It is — 

 36 93 lbs. below the average of the previous seven years. East winds alone, 

 were above the average both in frequency and force ; south-east, south- 

 west, and north-west, prevailed more frequently than usual, but all were below 

 the average force. North, north-east, and south, were below the average both 

 in frequency aud force. Calms were noted 36 times out of the 9J observa- 

 tions, and this is no less than -1- *16 above the average. No September, of the 

 previous seven years, had so many calms, though 1859 had a much smaller 

 wind-force, and 1860 also a little less. No wind during the month attained a 

 pressure to the square foot exceeding 2*60 lbs. 



Temperature mean was 53*34 degrees, being -f 2*42 above the 20 years 

 mean, and a little more than two degi-ees warmer than September 1863. The 

 mean by the self-registering maxima and minima thermometers, was nearly 

 the same as the foregoing, only exceeding it by *2l of a degree ; while the 

 usual variation is from one to two degrees. The maximum was 73 degrees, and 

 occur-ed on the 21st, with a light wind at 1 p.m. recorded south-east, though 

 the morning was noted north-west, and the evening north-east, but calm at 

 both observations. In no September since 1857 has so high a maximum 

 been registered. The minimum record was 38 degrees, which is higher than 

 that of any September of the previous 23 years, except 1845, which had 38*8 ; 

 and 1851, which had 39 degrees, The extreme range of 35 degrees in this 

 month, is less than that of any September of the previous nine years, except 

 1862, which had the same, though with both maximum and minimum each two 

 degrees less than the present month. The mean of all the maxima for this 

 monthwas the genial temperature of 62*46 degrees, while that of all the 

 minima was as high as 44 63 degrees. Modern research proves that too near a 

 correspondence between day and night temperature, is not the most pi'opitious 

 to health. Such a variation as that recorded for the present month, seems, as 

 far as our Hobai'ton records can establish the fact, the most favoralile to 

 health and life. The months of November and May are those in which this 

 conformity most usually occurs. 



The mean dairy range of temperature was, 17*83 degi-ees, which is only —'19 

 less than the 20 years average. The extreme range for any day occurred on the 

 21st, and was 29 degrees ; the smallest was 8 degrees on the 14th. 



Solar-intensity had the high mean of 90*70 degi-ees, being +2*75 degrees 

 above the avei'age of the previous eight years. The maximum was 105 degrees, 

 and recorded both on the 6th and 21st. Out of the previous eight years, only 

 1860 had so high a maximum. 



Terrestrial-radiation mean was, 40*73 degi-ees, which is -f 2*83 degrees 

 higher than the mean of the previous eight years, and warmer than any one of 

 them. The extremes were, maximum 49 on the 26th; minimum 31*5, on 

 the 12th. 



The total rain-fall of the month was only 1.25 inches being — "62 below the 

 September average ; but then the soil was so well saturated by the excessive 

 deposits in the three previous months, that this quantity, under the influence 

 of such hot sunshine, warm temperature of the soil,and genial air-teuiperature, 

 promoted vegetation in so great a degree, that never did our gardens snd 

 fields exhibit a more luxuriant and brilliant vegetation, in the month of Sep- 

 tember. At the same time the veinal influences on health were equally as 

 remarkably favorable ; a concurrence by no means usual. The number of days 

 on which rain is registered, were 11 ; which is — 455 below the September 

 average. On the, 14th and 24th, the rain fell smartly j^enough to cleanse the 

 jfutters and drains. Snow was never absent from Moiint Wellington during 



