98 



ANALYSIS OF THE OBSERVATORY RECORDS FOR 

 OCTOBER, 1866, IN CONJUNCTION WITH THOSE 

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



Though many of the meteorological phenomena were abnormal in 

 character this month, yet, on the whole, the weather was most auspicious 

 to health and life, and specially so to all children and young persons, 

 and even to adults under 60 years old. Very aged and weakly persons 

 constituted the principal mortality of this October, and in a greater pro- 

 portion to the total deaths at all other ages, than any other October on 

 record. 



Atmospheric pressure did not undergo any extreme daily variations, the 

 greatest being a fall of — '318 of an inch on the 8th, which is less con- 

 siderably than in any October of the previous eleven years. Nevertheless, 

 there were 13 days on which the barometrical movements exceeded one- 

 fifth of an inch. The maximum pressure, 30*315, was recorded on the 

 14th, and the minimum, 29*287, on the 10th ; so that in five days there 

 was a range of 1-028 inches, and more deaths occurred from 11th to 

 14th inclusive than any other consecutive four days in the month. The 

 mean of the month was 29*746, which is — -034 below the twenty years* 

 adopted standard mean for October. 



Wind-force was unusually moderate for this generally very boisterous 

 month. The total force was only 66-591bs., which is — 33-691bs. less than 

 the average of the previous nine Octobers. The diminution, moreover, 

 was in winds from those quarters least favorable to health. South-east^ 

 South, and West had all more than the average force, the other five points 

 had all less. The strongest winds registered had 5'211bs. pressure to the 

 square foot, and were recorded three times only. Calms were 21 times 

 registered, 14 of them being in the first week of the month. The nine 

 years' average is — 6*22 less. October 1865 had + 20-301bs. more wind- 

 force than the present month. No hot winds occurred,though it is probable 

 from some other of the phenomena that winds of that type prevailed on 

 the last three days of the month on the Australian continent. 



Temperature mean, 56-03 degrees, is 1-58 above the 20 years' mean fer 

 October, and + 2-36 more than October 1865 h'ed. The self-registering 

 maxima and minima thermometers gave a mean of only 55-37 degrees. 

 This is now the fourth month in succession in which this very nnuaual 

 discrepancy has been noted. The maximum was 90 degrees on the 31st. 

 Once before, during the previous 25 years, this thermometer attained 

 the maximum of 91-5. This was in October 1845. No other October 

 had a maximum exceeding 85-9. The maximum of the present month 

 occurred in a very remarkable manner : — Both the previous days were hot, 

 having maxima respectively of 81 and 82 degrees, — on the 31st at 7 a.m., 

 the observed thermometer was registered at 64, and at 1 p.m., 67. In the 

 interim did the intense heat of 90 degrees, recorded by the self-registering 

 thermometer, occur ? — and that was just before 10 a.m., for shortly after 

 that time a strong cold sea breeze set in, and reduced my ordinary 

 attached-thermometer 23 degrees in two hours, the barometer rising 

 rapidly at the same time. The mean of all the maxima, or high-day 

 temperatures, was 65*65 degrees, while 1865 was 65*58. The mean of all 

 the minima, or low-night temperatures, was 45*10 degrees, 1865 being 

 45-95 The minimum was 38 degrees, registered on the 14th, 15th, and 

 27th. Both 1865 and 1864 had the same minimum of 38. The month's 

 extreme range was 52 degrees, being the greatest recorded, with the 

 exception of October 1865, which had a range of 56 degrees. The self- 

 registering maxima and minima wet-bulb thermometers had a mean of 



