in medicine. See Medicine, p. 61.

**TERTIATE** a great gun, in gunnery, is to examine the thickness of the metal at the muzzle, whereby to judge of the strength of the piece, and whether it be sufficiently fortified. This is usually done with a pair of caliper-compasses; and if the piece be homed, the diameter left by the height, divided by 2, is the thickness at any place.