The inclosed Paper Contains a short sketch of Dr. Blacks Doctrine of Latent heat. It is there applied only to a few phenomena but the Dr. has experiments to shew that it is also the Cause of vapour, and He Explains How Evaporation Generates Cold, and the whole Theory of fluidity. After you have red this short paper, When you meet with my B[rothe]r He will give you the Extent of the Doctrine and Inform you of the Experiments by which It is supported.

This Paper I got from one of Dr. Blacks Students for the use of Monsieur De Morveaux. I am with the most thorough Attachment Dear Sir Your most obedient humble Servant