308 



Dr. A. Rattray on the Effects of 



[Feb. 16, 



Very different was the effect of the 44 days' continuation of the voyage to 

 Sydney along the 40th parallel of south latitude, after a health-infusing stay 

 of fifteen days at Simons Bay (Table X.). Although the usual sea dietary 

 was continued, the exit from the tropics was an evident relief to the system, 

 which, but for the diet, would have retained its vigour throughout. As it 

 was, only 26 } =19' 69 per cent., lost flesh slightly. All the boys, who had the 

 strong vital resilience of youth in their favour, gained in weight, and also 

 the younger men, while the seniors lost. An increase in the ingesta of 

 7 drams daily towards the end of the period is too trivial to have influenced 

 these results. This shows how long the system will ward off the scorbutic 

 diathesis when opposed by no other serious adverse agency, provided lime- 

 juice is given as a prophylactic. The increased sick-list and intensity of 

 the ailments, however, towards the end of the period, show that the immu- 

 nity was passing off. The difference in the percentage of those who lost 

 flesh in this and the former part of the voyage (Table IX.), is evidently 

 the effect of climate, and indirectly confirms Tables I. and II. 



To the bracing effect of the S. temperate zone we must chiefly ascribe 

 the recovery of the crew. Wasted while crossing the equator, only 29 per 

 cent, were below their original weight in England on arrival at Sydney. 

 This loss, though evident among the juniors, was chiefly among the adults 

 and older men (Table XL). The superior health and efficiency of a crew 

 in cool climates is an evident indication in planning long voyages. And 

 we have only to recollect the position and direction of the chief winds and 

 ocean-currents usually followed, to see how much these favour the mainte- 

 nance of health as well as rapidity of progress. 



Table XI. — To show the effect of a voyage of 144 days on the weight. 



Average temperature in England 50° F., Equator 88° E, Sydney 62° F. 



1st -weighing, January 9, 1864, in England, | 14zL f 27 in the tropics, 



2nd „ June 2, 1864, near Sydney, ] ^ aa ^ s [ 117 in temp. zone. 



Salt meat issued on 110 days 



(with 50 lime-juice days) 

 Eresh meat issued on ... 34 ,, 



Eood consumed per man daily. 



lb. oz. drs. 



Average of first week ... 1 12 13£ 

 last „ ... 2 5 11J 



Age. 



Total 

 number 

 weighed. 



Number 

 and 

 percentage 

 unchanged. 



Number 

 and 

 percentage 

 who gained. 



Eange 



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 



76 

 42 

 12 



per cent. 

 5=6-58 

 3 = 7-14 

 1=8-33 



per cent. 

 52=68-42 

 25=59-52 

 6 = 50 



lb. 

 1-18 

 1-15 

 3-7 



lb. 

 5-73 

 5-76 



5 



per cent. 

 19=25 

 14=33-33 

 5=41-66 



lb. 



1-25 

 1-15 

 1-14 



lb. 

 5-47 

 5-85 

 7-2 



















Totals 

 and per- 

 centages. 



130 



9=6-92 



83=63-85 



1-18 



5-69 



38=29-23 



1-25 



5-84 



92=7077 per cent. 



