5. _Inflation._--In the first place, it is to be remarked that to inflate the lungs is by no means an easy task. Elsässer states “that in forty-five experiments performed on children born dead, without opening their thorax and abdomen, only _one_ was attended with complete success, thirty-four with partial success, and ten with none whatever; and it must also be remembered that these experiments were conducted without disturbance, and with the greatest care.” Professor Gross states his opinion on this subject thus: “We are decidedly of opinion that artificial inflation of the lungs is a very difficult matter; and we believe that the complete distension of these organs can only be effected where a tube is introduced into the mouth of the larynx.” In the cases that come before the medical expert, the question naturally arises, Who would inflate the lungs? Surely not the mother. If not the mother, who else? It has been suggested that some malicious person might inflate them to sustain a charge of infanticide. Is this probable? The following points may be noticed on this subject: (_a_) Known difficulty in inflating the lungs. (_b_) Absence on the part of the mother of any preparation to save the life of her child. (_c_) Presence of air in the stomach and intestines, the result of attempted inflation. (_d_) Bright cinnabar-red colour of the lungs, without trace of mottling. (_e_) Absence of frothy blood when the lungs are cut into. (_f_) When, therefore, we observe the following phenomena, a sound of crepitation without any escape of blood-froth on incision, _laceration_ of the pulmonary cells with hyperæmia, bright cinnabar-red colour of the lungs _without any marbling_, and perhaps _air_ in the (artificially inflated) stomach and intestines, we may with certainty conclude that the _lungs have been artificially inflated_. It may be further noted that natural respiration is accompanied with, first, the distension of the air cells of the lungs with air; and, second, with an increased flow of blood into the organs, beyond that necessary for their nourishment and growth. They thus increase in absolute weight, while their specific gravity is lessened. The objections just mentioned apply to the hydrostatic test as originally employed. It will now be necessary to notice those against the same test when modified by pressure. These are two in number: 1. That no amount of pressure, short of entirely destroying the lung tissue, can expel the air from a lung that has been inflated, or from one in which respiration has taken place. 2. Pressure is, therefore, no test of natural respiration or of artificial inflation.