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MY BRF.ATHING SYSTEM

Dr. J. F. Halls Daily on the Diaphragm.

For thirtcen years I)r. Hall-; Daily has heen engaged in investigating the subject of respiration, both in human beings and animals. He has come nearer the truth than any other living man of science. Amongst other things, hc proved that the old theory as to the flattening of the diaphragmatic domes is pure fancy. He found that they move up and down after the fashion of a piston. In his clinical lecture, " Respiration in Health and Disease,” he says (p. 12) the following concerning the movement of the diaphragm :—

" For any adecjuate description of this moyement you will consult in vain most of the standard works on physiology. Until the present datę most of these works State that during inspiration the central tendon of the diaphragm re-mains fixed, while the domes flatten in dcscent, this supposed action being illustrated in man}' cases by imaginative diagrams. In point of fact no such action takes place, lt is trae that on orthodiagraphic examination in subjects with well-dcveloped diaphragmatic descent, a slight depres-sion is sometimes seen just extemal to the summit of the right dome, this being due to the strong downward puli of the right crus ; and that in some people with marked raising of the lower ribs the convexity of the dome represents the arc of a slightly larger circle that it does in expiration ; but with tliese minor exceptions, whieh I only mention for the sake of completeness, it is incorrect to state that any flatten-mg of the domes occurs. As I pointed out in 1903, the curve of the convexity on each side is unaltered in descent, and each half—although attached to its fellow of the opposite side by the central tendon —by means of its own separate innervation through the phrenic nerve, acts ąuite inde-pendently . .

Again, “ This second movement (a raising and lateral movement of the lower set of ribs) is also caused by the