With that talent for close observation and investigation which distinguished him, he pondered much over this remark of the milkmaid’s, and made many inquiries of the medical men of the district. From them he obtained but little encouragement; they had often heard the tale, but had not much faith in it. The subject seems to have impressed itself greatly on his mind; for we find him, some three years later, when he was in London with John Hunter, mentioning it to him; and that distinguished man appears to have been struck with Jenner’s earnestness in the matter, and gave him good advice: ‘Don’t think, but try; be patient; be accurate.’ This advice he perseveringly followed on his return to his native place; and by careful experiments elaborated the great life-saving truth, that cowpox might be disseminated from one human being to another to the almost total extinction of smallpox. The eastern practice of inoculation was first made known in this country by Lady Wortley Montagu, who was the wife of our ambassador at Constantinople, where she had seen it tried with good effect. Inoculation consisted in transferring the matter of the _smallpox_ pustule from the body of one suffering from the disease to that of one not as yet affected by the disease. It is a fact that the form of smallpox thus communicated through the skin was less severe, and consequently less fatal, than when taken naturally, as was abundantly proved in this country. But, unfortunately, inoculated smallpox was as _infectious_ as the natural smallpox—this fact forming the great distinction between inoculation and vaccination. The inoculated person became a centre of infection, and communicated it to many others. It was found after the introduction of inoculation that the mortality from smallpox increased from seventy-four to ninety-five in one thousand; and many of those that recovered, lost the sight of one or both eyes, or were otherwise disfigured. It is not to be wondered at, with such a state of things as this existing, and the whole medical profession at their wits’ end for a remedy, that Jenner should be looked upon, as soon as vaccination became established, as a saviour of his race.