558 REPORT—1905. 
chloroform with plenty of air,’ the percentage is found to be from 1 to 2 per cent., 
and the large amount of chloroform used and the free admixture with air produces 
a more nearly uniform supply to the patient’s lungs than when small quantities 
and a closer method, with its alterations of ‘ off’ and ‘on,’ are resorted to; and by 
means of densimeter determinations have shown that the ordinary percentage of 
mixture supplied by this rough method lies between the desired limits of ] and 
2 per cent. The great danger of this method is that, should the fabric be crammed 
down over the patient’s face, the percentage may rise to five times or more tke 
upper limit of safety. 
Of the different types of apparatus obtainable preference should certainly be 
given to those worked on the principle of supplying the anesthetic mixture freely 
by propulsion to an open and !oosely fitting face-piece rather than to those which 
are set in action by the inspiratory movements of the patient himself, because of 
the fact that if the respiration become weaker the vapour in the apparatus not 
being drawn over quickly enough becomes more strongly saturated, and a dangerous 
percentage may be suddenly reached. 
Given the requisite care and skill and knowledge on the part of the admini- 
strator, anesthesia may be properly carried out by any method. A folded towel 
drenched with chloroform can be safely used by an anesthetist who is fully alive to 
the extreme danger of two or three deep inspirations of a concentrated mixture, 
and who watchfully secures a free supply of air. On the other hand, a person 
unmindful of the physiological elements of chloroformisation is a dangerous ad- 
ministrator, however faithfully he may set the taps or turn the handle of the 
apparatus he may have thought fit to purchase. 
2. The Application of Food within the System viewed by the Light of 
' Modern Research. By F. W. Pavy, MD., LL.D., FES. 
The most superficial observation suffices to show that the growth and main- 
tenance of the body are dependent upon an adequate supply of food. Life is 
attended with, and may be said to result from, chemical changes, and a supply of 
material is required as a medium upon which the change can be brought into play. 
Building-up and breaking-down processes are constautly in operation, and to meet 
the demand arising therefrom there must be a supply of food. 
It may be taken as an axiom that it is within the tissue molecules that the 
utilisation of food occurs. The food must reach these molecules and become incor- 
porated as constituent parts of them before it can be turned to account. The 
manner in which it does so is the point to be considered in this communication. 
The doctrine hitherto entertained has been that the products of food digestion 
enter the blood and by its agency become conveyed to the tissues which take and 
subject them to direct application. To this doctrine exception will be taken. By 
modern research a new light has been thrown upon the chemistry of life, and 
viewed by this light a new aspect is given to the line of procedure connected with 
the application of food. 
Digestion, which constitutes the first step in the preparation of food for service 
in the system, must now be looked upon as consisting of something more than 
bringing to a state that absorption by osmosis may occur. It is necessary, it is 
true,that the food should be liquefied and broken down into small molecules, so as 
to be rendered diffusible and fit for penetrating the membranous layer of the alimen- 
tary canal. t is, however, also necessary that a certain configuration should be 
given to the molecules to adapt them for being taken on by the cell protoplasm 
which is instrtmental in absorbing and assimilating them, Molecules devoid of 
adaptability for being linked on to the living protoplasmic molecules would simply 
pass as inert matter through the body. For instance, cane sugar and milk sugar 
are not susceptible of being touched by protoplasm. In a dissolved state they are 
diffusible, and thus can readily pass through an animal membrane; but without 
transformation as a preparatory step to absorption they would fail to be assimi- 
lated, or, in other words, fail to be taken on by the living protoplasm with which 
