S8 REPORT — 1861. 



. The discipline enforced consisted of treadvvheel-labour on three days 

 weekly, from 7^ a.m. to Sj p.m., comprehending a period of 3i hours of 

 actual labour, and an actual ascent of 1"432 mile, and was equal to lifting SSI- 

 tons through 1 foot daily. On the alternate days the labour was oakura- 

 picking, or similar light occupation, and on Sunday there was perfect rest. 



The urine was collected in bottles which were used also whilst passing 

 faeces. Two collections only were made on Sundays, viz., those of the day 

 and night, but on the weekdays the urine was also collected separately, 

 from 6.15 to 7.15 a.m.; and on the treadwheel-days from 7.15 to 8.25, a.m. 

 These two latter sets of quantities were termed " basal quantities," since by 

 one it was hoped to determine the actual rate of urinary excretion in the 

 absence of food, and by the other the influence of treadwheel labour apart 

 from any other influence. The analyses for urea and chloride of sodium 

 were made by Dr. Smith ; but those of the food and faeces, and the final 

 analyses of the urine were kindly made by Mr. Manning. The samples for 

 analysis were taken with the utmost care. The details of this investi- 

 gation are very numerous; and probably it may sufl[ice to give the follow- 

 ing principal results of the inquiry. 



Urea, — The proportion of urea to each lb. of body-weight, both on 

 days of labour and on those of rest, was much above that found in the 

 ordinary conditions of life, viz., from 4"39 grains to 4'7'i grains, or an 

 average of 4'58 grains to each lb. of body-weight. It Avas less than 

 4 grains to each lb. on only one occasion in each of the lighter, and 

 on three occasions in each of the two heavier men, whilst Dr. Smith 

 found in himself with about the same food, but with much greater weight 

 of body, an average proportion of only 2*75 grains to each lb. The cause 

 as well as the significance of this fact is not clear; for, as it occurs with rest 

 as well as labour, it can scarcely be an evidence of increased degradation of 

 tissue, and as the food allowed is not much beyond that which a man in 

 health would ordinarily eat, it cannot be, the I'esult of an undue ingestion of 

 nitrogenous food. The probable explanation is that already referred to, viz., 

 that the nitrogenous tissues in the bodies of prisoners after a certain term of 

 imprisonment, bear a larger proportion to the weight of the whole body than 

 is found in health under ordinary conditions, since, by the labour and disci- 

 jjline of the jail, they have lost much of their fat and the fluid contained in 

 the tissues is reduced to a minimum quantity. The average weight of these 

 men was much below the ordinary weight of men of their age and height. 

 If this be the true explanation, the relation of urea to body-weight loses 

 much of its physiological importance. 



The urea excreted during treadwheel-labour before breakfast showed that 

 such exertion had no definite influence over the elimination of that product. 

 In one of the cases the excretion of urea was much greater than in the 

 others. There was some diversity in the quantities evolved by the others ; so 

 that in one they were the same in labour as at rest, in another there was an 

 excess of 2*5 grains per hour with rest, and in the 3rd there was an increase 

 of 1'9 grain per hour with labour ; but on the average, of all the three over 

 the whole period, there was '2 grain per hour less evolved with labour than 

 during rest ; and on the average of all the four prisoners, this defect was so 

 much as 2'4' grains per hour. There were numerous occasions on which 

 there was an excess with labour, viz. 28, 33, and 71 per cent, of the observation 

 in the three cases above separated. The greatest excess with labour was 

 7*5 grains, and the greatest defect with labour was 5*3 grains per hour, and 

 both occurred in the same person. 



As this inquiry occupied only 80 minutes at one time, it is very probable that. 



