Page:Popular Science Monthly Volume 27.djvu/405

Rh knee and with one blow of his paw broke the butterfly. To the old gentleman it was as to Sir Isaac Newton—the loss was great, and the shock must have been intense. Although I had hardly seen the specimen, I was profoundly affected by the mischance. But he neither struck the dog nor spoke loudly. With a trembling hand and flushed face he set to work at once to gather up carefully the disjointed wings of his specimen, which was happily accomplished, and, with a little gum and much patient dexterity, the damage which seemed at first irreparable was remedied. It taught me a lesson I have never since forgotten. The butterfly was the rare Papilio Calverleyi, of which up to the present time but one other specimen has been found. I have now new faith in that old story, from having witnessed a similar occurrence, and fresh belief in the goodness of that human nature which science and its pursuit often tend to strengthen and confirm.



IFFERENT epochs in life are marked by the frequency or infrequency of certain morbid phenomena constituting that departure from the normal standard of health which we denominate disease.

What is life? is the unanswerable question the human race has ever sought to solve. Bichat called it "the sum of the functions by which death is resisted." Physiologists of the present day offer little more that is satisfactory in their definitions, calling it "the aggregate of the phenomena peculiar to living organisms." The inscrutable mystery which surrounds the principle of vitality renders any attempt at definition illogical and unsatisfactory. We have to deal with the phenomena of life, and the functions through which these phenomena are manifested. In the child we have an exuberance of life. Manhood is the period of repose; waste and repair seem to neutralize each other; and calmness, deliberation, and quietude prevail.

With old age come disturbance, waste without repair, destruction without building up, action without reaction, decay and death. These phases of animal life are constantly repeating themselves. In discussing the diseases of old age, we have to deal with the phenomena of life, the perversion of functions which have hitherto counterbalanced each other. The prime of manhood and stability is passed; internal resistance now fails to maintain itself against external force. Nutritive action does not respond to the demand to renew effete material. The equilibrium being destroyed, decay and the products of decomposition become the most important factors in the study of the diseases which now threaten to disintegrate this hitherto self-sustaining system. 