PROOF, in Law and Logic, is that degree of evidence which carries conviction to the mind. It differs from demonstration, which is applicable only to those truths of which the contrary is inconceivable. It differs likewise from probability, which produces for the most part nothing more than opinion, while proof produces belief. See PROBABILITY.
The proof of crimes was anciently effected among our ancestors divers ways; viz. by duel or combat, fire, water, &c. See DUEL and ORDEAL.
PROOF of Artillery and Small Arms, is a trial whether they stand the quantity of powder allotted for that purpose. The rule of the board of ordnance is, that all guns, under 24-pounders, be loaded with powder as much as their shot weighs; that is, a brass 24-pounder with 21 lb. a brass 32-pounder with 26 lb. 12 oz. and a 42-pounder with 31 lb. 8 oz.; the iron 24-pounder with 18 lb. the 32-pounder with 21 lb. 8 oz. and the 42-pounder with 25 lb.
Proof. The brass light field-pieces are proved with powder that weighs half as much as their shot, except the 24-pounder, which is loaded with 10 lb. only.
Government allows 11 bullets of lead in the pound for the proof of muskets and 14.5, or 29 in two pounds, for service; 17 in the pound for the proof of carbines, and 20 for service; 28 in the pound for the proof of pistols, and 34 for service.
When guns of a new metal, or of lighter construction, are proved; then, besides the common proof, they are fired 200 or 300 times, as quick as they can be, loaded with the common charge given in actual service. Our light 6-pounders were fired 300 times in 3 hours 27 minutes, loaded with 1 lb. 4 oz. without receiving any damage.