THE LIVING MACHINE

New Zealand Times, Volume LI, Issue 11739, 29 January 1924, Page 2

THE LIVING MACHINE

* WONDERS OF THE BODY CO-OPERATION v. HARMONY. A SOCIETY OF MILLIONS OF CELLS. Julian S. Huxley, in the “New Leader,” draws a wonderful picture 1 of that wonderful living machine, the ‘ human body. “YVe are so apt to take things for granted that we hardly ever take time to reflect on anything so familiar as tho working of our own bodies,” he says. “Yet a man, or a dog or a rabbit, considered merely as things which v/ork, constitute pieces of machinery as much more complicated and astounding than a motor-car, as Is a motor-car than a pair of scissors. “The detailed adaptations of structure to function are remarkable enough—the way a joint works, the focussing of the eye, "the construction of the hand. These have been almost i among the commonplaces of science for some time, And have often been described. Of recent years, however, attention has been more and more drawn to the working of the maohine as a whole, to the way in which its different structures co-operate, their functions interlock, so that there results harmony and not chaos. “How is it possible that hand, foot and eye shall co-operate in the cricketer or tennis player? If our temperature goes up much over 5 degrees we Become delirious, if it sinks much below s_degrees we become unconscious. How is it regulated ? The cells and tissues will only work properly when bathed with a fluid of a certain acidity—how is that kept constant P How is it arranged that the digestive juices shall be poured out only when food is or that growth shall be equable, hot too much in one organ too little in another? ‘ ‘The regulation of the acidity of the blood is one of the beat illustration of the delicacy of the processes involved. In ordinary circumstances, blood acidity is determined by the amount of carbonic acid in the blood, and this in its turn depends chiefly on two things—on the rate at which it is being produced by the muscles, and : the rate at which it is being got rid of by the lungs. From one particular region of the base of the brain spring : the nerves which control the rate of \ breathing, and this ‘respiratory con- i tre’ is amazingly sensitive to changes in amount of acid. The least excess of 1 carbonic acid wilFTncrease its activity, which will inorease the rate of breathing, which will wash more carbonic ' acid gas out by the lungs. “Thus the respiratory centre is like the governor of a steam engine—a ■ piece of apparatus- which makes the whole machine self-regulating. But 1 its accuracy is inconceivably much i greater. An appreciable increase of rate of breathing is brought about by an increase of one part of acid (hydrogenion) in a hundred billion of blood ! ■ —so that the acidity of the blood of a healthy person retains a far greater constancy than almost any substance which the chemist can make. ... “All this has a lesson for us, both as individuals and as social beings and \ citizens. Our mind grows like our body, but it Is much more plastic, ; much less predetermined, more under t our own control. If such elaborate < mechanisms are need to raise our body * to the pitch of perfection (far above that of primitive animals) whioli it ne- ; joys, it is clear that equally elaborate , arrangements must be needed to bring , our mind to its full possibilities. , f “If-wo reflect that our body is a society of millions of millions of cells; that it is a machine whose present complexity and smoothness of working , have only been built up gradually in - the course of evolution, must wo not j then ask ourselves whether it would not bo possible to construct machinery of at least comparable smoothness in i the State and society, and so tn en- ] sure that efficiency of production on 1 the one hand, and on the other leisure and tho enjoyment of leisure shall £ be the result?” c