V. 



NOTES OX THE METEOROLOGY AND MORTALITY OF 



THE HOBART TOWN REGISTRATION DISTRICT DURING 



THE MONTH OF APRIL, 1872. 



By Dr. E. Swarbreck Hall. 



Tlie only meteorological phenomena of this month adverse to health 

 ■were excessively high daily-range of temperature and high eU'stic-force of 

 vapour. On the other hand, wind-force, tem^Derature, rainfall, serial purity, 

 were all propitious to health and life, and consequently the deaths in the 

 month were one-sixth less than the average of the previous 15 years' Aprils. 

 Atmospheric-pressure mean, 29"981, was only -f '069 above the 30 years 

 average for April. The maximum was 30 "302 on the 12th, the minimum 

 29*547 on the 6th, the extreme range of the barometer being therefore only 

 '755 of an inch- The greatest movement in any 24 hours was a fall of — '395 

 of an inch on the 13th. On eight other days the movements exceeded one- 

 fifth of an inch. 



Wind-force total, 53 "07 lbs., was, -1-6 '13 lbs., above the April average. 

 From the four healthiest points of the compass, S.E., S., S.W., W., the 

 winds, both in frequency and force, greatly predominated over the other 

 less favourable points. The strongest winds had a pressure of 5 '21 lbs. to 

 the square foot, and were recorded three times. Calms were registered at 

 32 out of the 90 observations, being +2 above the average. 



Temperature-mean, 56 '42", was -M'09 above the average, ^he maxi- 

 Jnum was 76 on the 19th, the minimum 38 on the 12th. The tvet-bulb 

 Thermometer had the mean of 51 '91°, being -fO'82 above the average. 



Daily-range of temperature, 21-83°, was -f-4'47 above the average. In 

 only two years out of the 30, in 1857 and 1858, was the daily-range higher. 

 Its effects were scarcely appreciable on deaths from diseases of the organs 

 of circulation and respiration, but the deaths from apoplexy and paralysis 

 were unusually numerous. The gi-eatest range on any day was 34 degrees 

 on the 12th ; the high day maximum of that day being 72 degrees, and 

 the low night minimum 38 degrees. 



Solar-intensity mean 90 '07 degrees, was — 1*67 below the average, the 

 cloudy days being above the average. The maximum was 105 degrees on the 

 16th. Only two Aprils in the last 18 years have had a lower maximum. 



Terrestrial-radiation mean, 42 '78 degrees, was - '91 below the average. 

 The minimum was 33 '5 degrees in the night of the 12th. 



Elastic-force of vapour mean, 338, was x 9 above the average. The range 

 was from 226 on the 12th tq 485 on the 24th. 

 Humidity mean, 75, was — 1 below the average. 



Rain- fall was 2 '01 inches, being x '24 of an inch above the average. 

 It fell on 9 days, being — I '70 less than the average. On two days, how- 

 ever, the rain was very heavy, i.e., half an inch on the 13th and nearly 

 three-quarters of an inch on the 20th, and nearly one-quarter of an inch on 

 each of the two following days, so that as far as rain-fall can cleanse our 

 drains, sewers, and city rivulet, they had this desirable advantage. Snmo 

 fell abundantly on Mount "Wellington on the 21st and 22nd, but was not 

 visible during the rest of the month. 

 Spontaneous evaporation amounted to 226 inches. 

 Cloud mean, 6 '59, was x '85 above the average. 



Ozone had the mean of 7 "41, which is x '35 above the average. Only 

 twice before in the previous 15 years has there been more ozone in April. 

 Satui-ation (10) was recorded 7 times. 



Electricity. — There were 15 "jjositive" records with tension 2 to 5. The 

 *' negatives'" were 26, with tension from 1 to 4. " Nils " were registered 16 

 times out of the 60 obsei-vations. 



T/twn(Ze?' was heard on the evening of the 4th. An Aurora was seen on 

 the evening of the 29th. 



The Deatlis were 35 in number, being — 6'7,5 less than the average of 

 the previous 15 years. Under one year old there were 6 deaths ; from 1 to 

 5 there was only 1 ; from 5 to 10 also 1 ; from 10 to 15 there were 2 ; from 

 15 to 20 none ; from 20 to 60 there were 14 ; at 60 and all ages above there 

 were 11 ; the oldest being 79 years old. In the Zymotic class of diseases, 

 ^here were 4 deaths, all from Diarrhoea. One of these, a child aged 7 months, 



