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forded by his residence in a dairy-country: for many others were similarly situated. Something was doubtless due to his taste for Natural History and his habits of observation, and more to the in- fluence of his great master John Hunter's example and well-known maxim— a brief paraphrase of Har- vey's injunction — not to think only, but to try; but most of all Jenner owed to his own modest and teachable spirit, 'that did not disdain the po- pular belief of unlearned peasants, but could admit it as a subject for scientific examination, and dis- cern in it a truth of matchless importance. It may not be amiss to notice, that the calm wisdom of Harvey had commended that very frame of mind which many years afterwards led Jenner to his happy discovery. Not only did Harvey en- join the searching out the secrets of Nature by way of experiment ; but this man, full of know- ledge, tells us :— " True philosophers never regard themselves as already so thoroughly informed, but that they welcome further information /rom ivhom- soever and whencesoever it may come"(j9). And "the studious and good and true... know full w^ell that many things are discovered by accident, and that many may be learned indifferently /rom any 2—2