Page:An Inquiry into the Causes and Effects of the Variolæ Vaccinæ - 1798.djvu/66

 These experiments afforded me much satisfaction, they proved that the matter in passing from one human subject to another, through five gradations, lost none of its original properties, J. Barge being the fifth who received the infection successively from William Summers, the boy to whom it was communicated from the cow. I shall