"The small-pox, so fatal, and so general amongst us, is here entirely harmless, by the invention of engrafting, which is the term they give it……… She immediately rips open (the vein) you offer to her…..and puts into the vein as much matter as can lie upon the head of her needle , and after that, binds up the little wound with a hollow bit of shell, and in this manner opens four or five veins..….. The children or young patients play together all the rest of the day, and are in perfect health to the eighth. Then the fever begins to seize them, and they keep their beds two days, very seldom three. They have very rarely above twenty or thirty in their faces, which never mark, and in eight days time they are as well as before their illness…… Every year, thousands undergo this operation, and the French Ambassador says pleasantly, that they take the small-pox here by way of diversion, as they take the waters in other countries. There is no example of any one that has died in it, and you may believe I am well satisfied of the safety of this experiment, since I intend to try it on my dear little son….." (Montagu 167-169)
"In 1717 Lady Montagu arrived with her husband, the British ambassador, at the court of the Ottoman Empire. She wrote voluminously of her travels. In this selection she noted that the local practice of deliberately stimulating a mild form of the disease through innoculation conferred immunity.” (Internet Modern History Sourcebook)