56 



ANALYSIS OF THE OBSERVATOKY RECORDS FOR JUNE, 1864 ; 

 IN CONJUMCTION WITH THOSE OF BIRTHS, DEATHS, kc. By 



E. SWARBRECK HaLL. 



June commenced with such a genial fall of rain, that excited hopes that the 

 mortuary record of the month would fall below the average ; but the 

 subsequent weather was so abnormal in many respects, that again, for now the 

 fourth month in succession, the deaths are considerably above the average of 

 the previous seven years' Junes, 



Atmospheric 2^^'^ssure had a mean, 30*031, which has only been exceeded 

 twice in the previous 23 years :— 1863, 30-002 ; 1858, 30-057. 1854 had exactly 

 the same mean, and every other year, except 1859, had a mean below 30 inches. 

 The present month is + 00 164 above the 20 years' adopted standard mean,bufc 

 + 00 77 higher than the average of the first 14 years of the series. The extreme 

 range of the month was, 1-094 inches, and happened within three days, 

 the minimum, 29-291, having occurred at the evening record of the 7th; 

 and the maximum, 30 -38.5, on the morning record of the 10th. The fluctuations 

 of pressure were both numerous and high, the highest being a fall of — -715 

 of an inch on the 24th. Ou the 4th there was a fall of — 234 of an inch, and 

 next day a further fall of — 437 of an inch, making a total fall of — -671 in 

 the 48 hours. The greatest rise on any day was +• "690 of an inch, on the 

 9th. But the most remarkable condition of the barometer was observed 

 between the evening of the 24th and the close of the month, during which 

 the mercury contiuuouslj rose ; ou the 26tli as much as + '542, and for the 

 six days altogether + -912 of an inch. At the same time the temperature 

 was the highest for any similar period of the month. The ozone the same, 

 and yet the wind vane marked, mostly, northerly winds and of considerable 

 force. The last seven days of the month had the greatest number of deaths, 

 20, The previous seven had only 13, though one day, the 21st, had seven of 

 that number. That day had a high, and rising atmospheric pressure, without 

 wind, low temperature, cloudy, electricity almost absent, and ozone much 

 below the month's mean. 



Wind force total was, 28-60 lbs, only the Junes of 1857 and 1861 having 

 more the former being, 37-28 lbs., the latter, 29.04 lbs. The present month's 

 force exceeded the average of the seven previous years, by + 3-83 lbs. ; yet 

 the calms, 46, were + 3 above the average ; thus showing that the winds 

 were of unusually great force, when there were any. S.W., W., and N. W. 

 were all above the average both in frequency and force. The latter was 

 recorded 43 times out of the 90 observations, and as having 10-92 lbs. out of 

 the total force. But as I have often before remarked, the coast, &c. stations, 

 at the same time recorded west or south-west winds, there being no doubt 

 that the course of the valley of the Derwent, with the position of Mount 

 Wellington, frequently causes a north-westerly deflection of what are really 

 winds from the west and south-west points of the compass. North winds 

 were considerably below the average frequency, though nearly one poimd 

 above the mean in strength. N.E. winds were nearly as much above the 

 average in frequency, as north were below, but were a few decimals below the 

 mean in torce. From all the other three points of the compass, the winds 

 were below the average, both in number and strength. The gre-itest force 

 of any wind during the month was 2-60 lbs.— twice noted from the south, 

 with the rain on the 1st. Once N.W. on the evening of the i5th, the same 

 from the noith at noon of the 6th, and from the west on the evening of the 

 24th and noon of the 25th. 



Temperature mean by the three daily observations was, 47' 43 degrees, 

 being + 00'30 above the 20 years' mean. The Wet-bulb-thermometer approxi- 

 mated unusually near to the foregoing, being 44-86 degrees. The present 

 month's mean, however, is + 2' 15 desrees above the 14 years' mean of the ob- 

 servations at the Royal Observatory Ross Bank, in the Queen's Park. The 

 maxima and minima thermometers give a mean of 48 '66 degrees. The highest 

 record of the former was 65 degrees, on the the 29th, the three previous days 

 were all 60, and the one succeeding was 63. No other day of the month 

 reached 60, except the 3rd, which attained 61. The mean of all the 

 maxima is only 56-23 degrees, so that the warmth of the last five days of 

 the month was peculiarly great. The minimum record was 32 degrees on the 

 10th and 13th, and the mean of all the minima of the month, 41-10 degrees. 

 1863 had the same minimum, 1862 had 29, 1855 had 31, all the rest of the nine 

 years had higher minima, than the present, and the whole nine higher 



