Two essays on the nature and wonderful properties of island crystal. ... The whole illustrated with copper plate figures. By Benjamin Martin.
Martin, Benjamin,1705-1782.
London : printed for, and sold by the author,
[1774?]
Both essays could be had separately, the first essay without titlepage.
Date of publication based on date of advertisement at the end: Just published, The description and use of an opake solare microscope. ... London: printed for the author, No. 171, in Fleet-Street, 1774.
The second section, with separate titlepage, pagination and register, is 'Essay II. on the nature and wonderful properties of island crystal. ...', with same imprint.
ESTC