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ANALYSIS OF THE OBSERVATORY RECORDS FOR 

 SEPTEMBER, 1865, IN CONJUNCTION WITH THOSE 

 OF BIRTHS, DEATHS, &c. By E. Swarbreck Hall. 



The weather generally this month waf favorable to health and life, beneficial 

 to agriculture and hoiiiiculture, and agreeable to the feelings ; being warmer 

 and less boisterous than usually characterises this vernal month of the southern 

 hemisphere. Nevertheless in some of the atmospheric phenomena, conditions 

 existed for brief periods, which had a lethal effect on individuals enfeebled by 

 sickness or old age. On the average of eight years, September is sixth on the 

 list of the twelve months, in its rate of mortality. Many persons erroneously 

 imagine that it is one of the most fatal to life. The present month's deaths 

 were below the September average numerically. 



Atmospheric pressure mean, 29705, is— '073 below the September average of 

 the twenty years' standard tables. Last year's September was about the same 

 in excess above the mean. The extreme range was, however, much less in this 

 month, than in that ; being only '874 of an inch, though it occurred within two 

 days, the maximum, 30*149 being registered at 7 a.m. on the 9th, and the 

 minimum, 29 '275, at the evening observation of the 11th. No September 

 in the previous five years had so small a raage. On the other hand the 

 daily perturbations weie both extensive and frequent. The greatest variation 

 in any twenty-four hours, was a rise of + '494 of an inch on the 8th, and a fall 

 of nearly as much, — "478, was recorded on the 20th. On thirteen days of 

 the month, movements exceeding one-fifth of an inch were noted. These 

 changes have always a marked effect on chronic diseases particularly of the cir- 

 culatory, respiratory, and nervous systems. 



Wind force toidl was, 48'63 lbs., which is — '26 '79 lbs. less than the Septem- 

 ber ayerage of the previous eight years, at the same time, September last year 

 had a few pounds less than the present month. The strongest wind had a 

 pressure of 5 '21 lbs to the square foot, but was only registered once, i.e., at 

 noon of the 25th, being a west gale. This month had somewhat of the character 

 which the English March bears, in " coming in like a lion, and departing like 

 a lamb." South-west and north-west winds had more than the average in fre- 

 quency, while all but the South were below the average in force. Calms were 

 recorded 21 times, which is — 3' 57 less than the mean of the previous seven 

 years. 



Temperature mean was, 52 '32 degrees, being -f- 1'40 above the 20 years* 

 average, though more than a degree below that of last year. The self -register- 

 ing thermometers gave a mean of 53-45 degrees, the variation being about what 

 is usual between these distinct modes of observation. The maximum was 74 

 degrees on the 20th, being from one to five degrees higher than in any September 

 «ince 1857. The minimum was 35 degiees, registered on the night of the 17th. 

 Last year's minimum was higher by three degeees, though its maximum was 

 one less. The extreme range, 39 degrees, exceeded any of the previous four 

 years by two to four degrees. The mean of all the maxima or high-day 

 temperatures was, 63 '27 degrees, curiously enough showing warmer days than 

 September 1864 had ; while the mean of all the minima or low-night tempera- 

 tures was 43 '63 degrees, and exactly one degree less than was noted last year. 

 The analysis of the daily observations and still more of the hourly, — as recorded 

 for eight years niglit and day at the Ross Bank observatory— give abundant 

 proof of the little reliance that can be placed upon general means, in deducing 

 effects on health and life. 



The daily -range of temperature h&d. the very high mean of 19 •63 degrees, 

 being + 1*61 above the 20 years' average, and above any of the three previous 

 Septembers, exceeding that of last year, by nearly two degrees. From the 

 remarks in the previous paragraph on day and night temperatures, this result 

 of course was obvious. Nevertheless, it is remarkable, that the extreme range 

 of the present month, 29 degrees on the 20th, was the same as for last years' 

 September. On the other hand the minimum range in the present month is 

 two degrees less (8) than last year. It used to be the prevailing belief in Eng- 

 land, that rapid transitions of temperature were the principal cause of diseases 

 and death, —and " took cold " became the ready explication of every death 



