of the Shot; as likewise that to Shot of the same Velocity and Matter, but of different Sizes , it should be as the Diameters reciprocally : Whence generally the Opposition to Shot with the same Velocity , but of differing Diameters , and Materials , should be as their Specifick Gravities into their Diameters reciprocally ; but whether the Opposition , to differing Velocities of the same Shot, be as the Squares of those Velocities , or as the Velocities themselves, or otherwise, is yet a harder Question. However it be, 'tis certain, that in large Shot of Metal , whose weight many Thousand times surpasses that of the Air , and whose force is very great, in proportion to the Surface wherewith they press thereon; this Opposition is scarce discernable; For by several Experiments made with all Care and Circumspection with a Mortarpiece , Extraordinary well fix'd to the Earth on purpose, which carried a solid Brass Shot of four Inches and a half Diameter , and of about fourteen Pound Weight, the Ranges above and below forty five Degrees were found nearly equal; if there were any difference, the under Ranges went rather the farthest, but those differences were usually less than the Errors committed in ordinary Practice, by the unequal Goodness and Dryness of the same sort of Powder, by the Unfitness of the Shot to the Bore, and by the Loosness of the Carriage.
In a smaller Brass-Shot of about an Inch and half Diameter, cast by a Cross-Bow which ranged it, at most about four Hundred Foot, the Force being much more equal than in the Mortarpiece, this difference was found more Curiously: and Constantly and most Evidently, the under Ranges out-went the upper. From which Trials I conclude, that although in small and light Shot, the Opposition of the Air, ought and must be accounted for; yet in Shooting of great and weighty Bombs, there need be very little or no allowance made; and so these Rules may be put in practice to