Here's a PDF of the original document from Archive.org -- I can't as yet find the full transcript - if anyone locates a text version, please post a link in this thread.
A sermon on natural religion. By a natural man. 1771 : Natural man : Free Download, Borrow, and Streaming : Internet Archive
A sermon on natural religion. By a natural man. 1771..Digitized from IA40310308-45.Previous issue:...
archive.org
One of the things about this which Matthew Stewart comments on is how interesting it was to the deists of this period to think about life on other planets and throughout the universe, and that this is in fact how the "Sermon On Natural Religion" ends: