1871.] 



Change of Climate on the Human Economy. 



301 



The following experiments to illustrate this were made in H. M.S. { Sala- 

 mander,' during a voyage of five months to, and a subsequent stay of three 

 years on the east coast of Australia, while making triannual trips between 

 Sydney (lat. 34°) and Cape York, Torres Strait (lat. 10J° S.), a distance of 

 1700 miles in a nearly north and south direction. The crew numbered 

 209, their ages being : — 



between 15 and 25 (period of growth) 129 (01*72 per cent.). 



25 „ 35 (adult age) 63 (30*14 „ ). 



„ 35 „ 45 (1st period of decline) ... . 16 (7*66 „ ). 



„ 45 „ 55 (2nd „ „) 1 (0-48 „ ). 



Thus 192 (91*86 per cent.) were under thirty-five, which may be con- 

 sidered the prime of life am wig seamen ; while the whole were healthy. 

 They were weighed as far as possible in the same clothes, and between 

 6 and 7 p.m., about two hours after a light " supper" of tea and biscuit, 

 in order to reduce error from variations in the state of the bowels, stomach, 

 bladder, &c, to a minimum. Their faulty diet, however, unmodified for 

 temperature, and containing salt meat and other hurtful articles, was an 

 unavoidable disadvantage. Fortunately this enables us to observe the effect 

 of an agency far more under control for modification or removal than climate. 



Table I. — To show the effect of Tropical "Weather alone on the weight. 



1st weighing, July 2, 1866, on entering tropics, \ 

 )ber 18, 1866, on quitting tropics, ' 



Aven 



2nd „ October 18, 1866, on quitting tropics, / 108 da ^ s ' aU s P ent in the tro P ics ' 



e temperature at Sydney 60° F., at Cape York 82° F. 



Food consumed per man daily. 



lb. oz. drs. 



Average of first week ... 2 5 12f 

 last „ ... 2 2 9| 



Salt meat issued on 36 days 



(with 61 lime-juice days) 

 "Fresh meat issued on 72 ,, 



Age. 



Total 

 number 

 weighed. 



Number 

 and 

 percentage 

 unchanged. 



Number 

 and 

 percentage 

 who gained. 



Range 



of 

 gain. 



Ave- 

 rage 

 gain. 



Number 

 and 



percentage 

 who lost. 



Range 



of 

 loss. 



Ave- 

 rage 

 loss. 



15 to 25 

 25 „ 35 

 35 „ 45 

 45 „ 55 



35 

 39 

 9 

 2 



per cent. 

 3= 8-57 

 3= 7-7 



1=50 



per cent. 

 13=3744 

 8=20-51 

 2=22-22 



lb. 



1- 8 



2- 10 

 1-2 



lb. 



3 



3-37 

 1-5 



per cent. 

 19=54-28 

 28=71-8 . 



7 =77-77 



1=50 



lb. 

 1-14 

 1-12 

 1-17 



lb. 



5-16 



4- 7 



5- 71 



5 











Totals 

 and per- 

 centages. 



85 



7= 8-24 



23=27-06 



1-10 



3 



55 = 64-71 



1-17 



5 



30=35-3 per cent. 



Table I. shows the effect of 3| months' exposure to an average tempera- 

 ture of 82° F. towards Torres Strait. Of 85 weighed, 64 \ per cent, had 

 lost flesh to an average of 5 lbs. Though greatest among the adults 

 (71 per cent.), and especially the higher ages (77 1 per cent.), it was large 

 even among the juniors, of whom 54 per cent, instead of growing, lost con- 



