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was passed in the fæces per man daily; with 6.5 grms. 0.43 grm.
passed in the fæces per man daily.
(v) It will be noticed that a larger quantity of NaCl was eliminated in the
urine and fæces than was present in the intake during the period
that the prisoners were getting 6.5 grms. daily. The excess derived
from the salt stored in the body, over the four days we have taken
into consideration, is very small—only 3.89 grms. for the batch of five
men, or 0.78 grm. per man. However, if we take the "transition
day"—the period before salt equilibrium is established—into consi-
deration, the excess works out to 15.25 grms. per man over the
five days. This excess is of course not entirely due to salt stored
up in, the body, but is simply the remains of the salt from the pre-
vious day's supply which had not yet been eliminated. We have not
taken the " transition day " into our reckoning.
(vi) There is no doubt that a considerable quantity of salt is eliminated by
the perspiration in hot climates like India. In our first period this
formed 11.6 per cent. of the total, or 2.37 grms. per man daily ;in
the second period it was not possible to calculate the amount eli-
minated by the sweat as the total intake of salt was not sufficient to
maintain salt equilibrium. It is highly probable that the quantity
of salt got rid of by the skin depends on the total amount of the salt
intake. When this is considerable thirst is raised, and the inges-
tion of large quantities of water increases the action of the skin ;
under the opposite conditions the skin does not act so freely, and
therefore smaller quantities of salt will be excreted by it.
(vii) The enumeration of the red blood corpuscles shows a decrease with the
decrease in the salt intake. This decrease we did not expect, and
it is at variance with our results obtained from experiment on
animals in the laboratory, where the conditions were more under
control than in the jails. Further, the limit of error in blood counting
is high—quite up to 5 per cent., and the count involves a great deal
of labour when batches of five men are made use of. The method
we prefer, and the one made use of in the laboratory is by means.
of the high-speed electric hæmatocrite, to determine the percentage
volume of the corpuscles under different conditions of salt intake
This we found impossible to carry out in the jails visited. Further
work will be necessary on the question whether the intake of salt
causes an increase or decrease in the number of the blood corpuscle
before any definite statement can be made.