Page:The Harveian oration ; delivered at the Royal College of Physicians, June 26th, 1879 (IA b24976465).pdf/25

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study any subject in nature the less isolated do we find it, so that all our ologies appear but the expressions of human weakness, and we are forced to declare that all nature is one.

"From nature's chain whatever link you strike,
Tenth or ten thousandth breaks the chain alike."

We look at the earth's crust and we perceive that it has been gradually formed, layer by layer, and, judging by the present rate of progress, that this has been in process for countless ages. We sce remains of animals, now extinct, in the earlier formations, and others nearer the surface which had no existence in the lower depths. In the history of man himself we observe the same progression, and whether we take his propensities, passions, or mental faculties, we see the same law in operation. It may be language or any other of his attributes which we are studying, but it forms only one link in the great chain of phenomena, proving that our carth is going onward in the course of development. From any point of view we take, and upon whatever subject we fix our gaze, we come to the conclusion that the greatest discovery ever made by man about himself, and of