Volume 2

Health lectures for the people.

Date:
1883-1892
Catalogue details

Licence: Public Domain Mark

Credit: Health lectures for the people. Source: Wellcome Collection.

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    food is taken, how food is digested, and the rules which should regulate healthy digestion in all its phases. If, therefore, we can gain some broad, even elementary, idea of these points, we may claim to have laid the foundation of a study in physiology of a most interesting kind. One of the most interesting subjects the physiologist can bring before a popular audience in answering the question I have just proposed, is that phase of human life which consists in the fact that a human being, or indeed any animal (and we might include any plant as well), is in a state of continual change, resulting from the work which, as a living body, it performs. For, at no period of our lives are we exempt from wear and tear. All the actions of life, from the pulsation of the heart to the winking of an eyelid; from the taking of a step, to the lifting of a finger—nay, more, even those subtle changes which pass through the grey matter of our brain, and which are evolved ultimately in the form of muscular action, and in the still more subtle essence of thought—involve wear and tear to the being which is subject to them. This question, Why do we eat our dinner? may be shortly answered by saying that the dinner represents matter drawn from the outer world, and calculated to repair the loss to which, in the act of living and being, we are continually subjected. It is very evident if the human being is a machine which is constantly working, it must be subjected to continual repair. Take even the case of a sleeping man—the rise and fall of the chest, the quiver of an eyelid, the faint movement, it may be, of a hand, show you it is not death, but death's twin brother, sleep, you are contemplating. Although the man is resting from his labours, and though he is enjoying the repose of sleep, it may be said in another sense, that his body is the seat of constant activity. For you cannot still that wonderful pump- ing mechanism, the heart, which is engaged long before w^e are born and up till we die, in circulating the vital fluid through our system. Even the dreams which haunt us in our sleep, evince that you have a certain amount of brain-activity in repose; so whilst we repair the body in sleep we are still wasting its sub-