From Benjamin Waterhouse
Cambridge August 1st. 1801.
Vaccine matter on the tooth-pick taken July 31.st. in the evening. The thread taken at the same time.—The two plates of glass, which he1 have covered with lead is just come to hand from Dr. Jenner being taken May 19th. in London. Two other plates containing some of the virus taken at the same time has been proved to be perfectly active. It adheres to the glass like gum. water, warm steam, or a little hot water is necessary to dilute it for use.—Dr Waterhouse is anxious to hear from Washington respecting the success of his endeavours—
RC (DLC); endorsed by TJ as received 13 Aug. from Waterhouse, and so recorded in SJL.
1. Word interlined in place of “I.”