According to historian Francis Parkman, Amherst first raised the possibility of giving the Indians infected blankets in a letter to Colonel Henry Bouquet, who would lead reinforcements to Fort Pitt. No copy of this letter has come to light, but we do know that Bouquet discussed the matter in a postscript to a letter to Amherst on July 13, 1763:
P.S. I will try to inocculate the Indians by means of Blankets that may fall in their hands, taking care however not to get the disease myself. As it is pity to oppose good men against them, I wish we could make use of the Spaniard's Method, and hunt them with English Dogs. Supported by Rangers, and some Light Horse, who would I think effectively extirpate or remove that Vermine.
On July 16 Amherst replied, also in a postscript:
P.S. You will Do well to try to Innoculate the Indians by means of Blanketts, as well as to try Every other method that can serve to Extirpate this Execrable Race. I should be very glad your Scheme for Hunting them Down by Dogs could take Effect, but England is at too great a Distance to think of that at present.
On July 26 Bouquet wrote back:
I received yesterday your Excellency's letters of 16th with their Inclosures. The signal for Indian Messengers, and all your directions will be observed.
We don't know if Bouquet actually put the plan into effect, or if so with what result. We do know that a supply of smallpox-infected blankets was available, since the disease had broken out at Fort Pitt some weeks previously. We also know that the following spring smallpox was reported to be raging among the Indians in the vicinity.
To modern ears, this talk about infecting the natives with smallpox, hunting them down with dogs, etc., sounds over the top. But it's easy to believe Amherst and company were serious. D'Errico provides other quotes from Amherst's correspondence that suggest he considered Native Americans subhumans who ought to be exterminated. Check out his research for yourself at www.nativeweb.org/pages/l egal/amherst/lord_jeff.html. He not only includes transcriptions but also reproduces the relevant parts of the incriminating letters.