ANALYSIS OF OBSERVATORY KKCOKDS, AND HEALTH REPORT 



FOR APRIL BY DR. E. SWARBRECK HALL. 

 In most respects the climatic character of this month has deviated widely from 

 the normal standard, tliough on tin* whole most favorable to health and life. 



BaroiiH'trical prciniirc mean, ;><) 01") was + 'LM above the mean for April. 

 Only three times in the previous 2\) Aprils has this high mean been exceeded, 

 and that by veiy little. Altogether in the liO years, the mean has only 

 reached 80*000 and u])wards eight tines. At the same time the extreme range 

 for this month was only 'SJiJof an inch ; tlie extremes being :i0'411 maximum 

 on the .5th, and on the 2}rd, minimum 29 "oS."). Equable high ])ressure was, 

 therefore, the character of the b iroinetrical records. Such phenomena are 

 generally associnted with an epidemic constitution of the air, but at this 

 time such a tendency was checked by a copious rainfall, and the unusual pre- 

 dominance of sea breezes. 



Wind- force had only a total of 21-32 lbs., being 25-30 lbs. below the April 

 mean. Fifty-five out of the 90 records, were winds from the southerly points 

 of the compass, with about two-thirls of the total force. South-east winds, 

 the healthiest jioint, were 40 in numljer, being 2J above the April average, 

 and with an aggregate force four times greater than usual. North-west, the 

 least healthy point, was about the average in number, but much below it in 

 force. Calms were 37. being 7 above the average. 



Mean Temperature, both l>y the three daily observations and the maxima 

 and minima self -registering thermometers, accorded more closely than usual ; 

 the former being 57 21 degrees, the latter 57-02. The mean is + 2-18 above 

 the average for April. The daili/ range, 13-97 degrees, however, was — 3-25 

 less than the 25 years' average. Only two years in the previous 29 had a 

 smaller daily range ; i.e., 1S51 with 11 "00 degree.s, 1852 with 12*60. The ex- 

 tremes also were not great, maximum being 78 at mid-day on the 7th, 

 minimum, 40 in the night of the 25th. 



Solar I at emit y mean 86-13 was — 5"68 degrees below the average, owing to 

 the very cloudy and wet character of the month. 



Terrestrial Radiation^ on the other hand, was -f 4*50 above the mean, being 

 47-57 degrees. 



Elastic-force of Vapour ranged from 207 to 633, with a mean of 374, which 

 is -h 49 above the average, and would have been inimical to health, but for 

 humidity and rain-fall. 



Humidity mean, 81, was + 5 above the average. 



Rain- fall 4-25 inches was + 2-47 above the April average, and fell in such 

 a way as to be most beneficial to health and vegetation ; copious enough to 

 cleanse the sewers, water courses, &c. , yet not not so heavy as to cause floods, 

 and commencing so gently as to saturate the soil gradually. The number of 

 wet days, 13, were only slightly ( + 1-18) above the average. Only two Aprils 

 in the previous 29 years had a greater rain-fall, 1856 with 5 '01 inches, 1852 with 

 4-99 inches, 1860 -ndth 2-86 inches, was the next highest. Notwithstanding 

 the dry character of February and ]\Iarch, the fall of rain on the aggregate 

 of the first four months of this year exceeds the average by -h 3 '61 inches. 

 Snow existed on Mount Wellington on the 22rd and 24th. 



Spontaneous-evaporation, with so little sunshine and winds, and so much 

 rain and clouds, was much less than rain-fall, i.e., 3 '19 inches. 



Cloud mean, 7 '13, was -\- 1-39 above the average, contrasting remarkably 

 with the previous month of March. 



O^one mean, 7 '01, barely exceeded the average, notwithstanding the heavy 

 rainfall and frequent sea-breezes. The gentle character of the latter accounts 

 for this. 



Electricity of a positive character was very small, and nils very numerous. 



There were only 34 deaths, being nearly — 10 less than the April average 

 of the previous 13 years. Seven (7) of these were under 1 year old ; two (2) 

 from one to five, none from that to twenty-two, but between that and sixty, 

 sixteen (16), the rest (9) were from sixty-eight to eighty-five years old. A girl 

 aged twenty-two died from Typhoid-fever, and there was only one other death 

 in the Zymotic class, a child aged three months, from Diarrhcea. Consumption 

 caused four deaths, none of them born in Tasmania. Scarlet-fever of a mild 

 type was pretty general, but without a death. Cutaneous diseases were very 

 prevalent, a result no doubt of the previous long-continued dry weather. 



