The arte of gunnerie. Wherein is set foorth a number of seruiceable secrets, and practical conclusions, belonging to the art of gunnerie, by arithmeticke skill to be accomplished: both pretie, pleasant, and profitable for all such as are professors of the same facultie. / Compiled by Thomas Smith of Barwicke vpon Tweed souldier.

To know the different force of any two like peeces of Ordi∣nance planted against an obiect, the one being fur∣ther of from the said obiect then the other.

Question.

Admit there is a Castell or Fort to be battered, being situate vpon a hill, which hill is 50 paces in height, and that 140 paces from the said Castell there is ano∣ther hill, of equall height to that hill whereon the Castell is built, and Ordinance planted thereon to beat or bat∣ter the Castell wall, and in the valley at the foote of the said hill 180 paces off from the Castell hill, there is Or∣diance planted, and mounted at 20 degrees, to shoot and beat downe the said castell: I would know whether the Ordinance in the valley being 180 paces distance from the Castell, and mounted at 20 degrees, or the Or∣dinance on the height of the hill, lying leuell to shoote a litle aboue the base of the wall, being distant therefrom 140 paces, shall worke the greatest effect in battering downe the said Castell wall, the said peeces being of like length and height, and hauing like charge in powder and bullet?

Resolution.

To resolue this or the like, a man would thinke that the peece planted on the height of the hill, lying leuell to shoote a litle aboue the ground-worke of the Castell, would batter sorest, because she is nearest: yet by expe∣rience we find the contrary, for the Castell being a great way within the reach of both the peeces, that peece shall not onely shoote much further, that is any thing eleua∣ted, but also pierce much sorer, by so much as she is able to ouer shoot the other selfe like peece that lyeth leuell:

albeit the said peece so eleuated, be planted furthest off from the said resisting obiect: for euery Gunner know∣eth, and reason and experience doth teach euery reasona∣ble man, that no peece of Artillerie will shoote so far at point blanke, as when the same is eleuated at any num∣ber of degrees; because the bullet being ponderous, fli∣eth more heauily and sooner declineth, being shot out of any peece lying leuell, then out of any such like peece mounted at any degree of the randon. So that of force it must needs follow, that the peece planted in the valley 180 paces off from the Castell, shall pierce and batter a great deale sorer then the like peece planted on the height of the hill being but 140 paces from it.

Example.

[illustration]

Example.

Suppose a Cannō or Culuering at point blanke shoot 240 paces, and being mounted at one degree outshoote the same 30 paces, what will the sayd peece do being mounted 20 degrees?

By proportion I find, that if at the mount of one de∣gree, any bullet range 30 paces beyond the leuell range, that at 20 degrees if shall outflie the same 600 paces: al∣beit the sayd bullet range not in euery degree a iust like number of paces, yet the proportion will be very neare thereto. And because the peece at the foote of the hill is sayd to be 40 paces further from the Castell, then the like peece planted on the height of the hill, I abate 40 out of 600, rests 560 paces: so farre would the peece in the valley out shoote the other like peece on the hill; so that it must needs follow, her bullet shall pierce so∣rest, for that it hath most strength to flie furthest.

Another exmaple or triall of the for∣mer conclusion.

The peece planted vpon the hill, is sayd to be 140 pa∣ces from the Castell, and the like peece at the soote of the hill 180 paces. Now suppose each of those peeces being layd at point blanke, would not range aboue 240 paces, abate 140 paces (the length to the marke of the peece on the hill) from 240 paces her leuell range, and the remaine is 100 paces; and so many paces shall that peece strike the marke before the end of her leuell range.

Now to find the like in the peece planted in the val∣ley 180 paces from the Castell, mounted at 20 degrees,

I find by the conclusion afore set downe, that she shall out shoote the other 600 paces: so that abating the di∣stance from the peece to the Castell, being 180 paces from 840 paces, her whole range mounted at those de∣grees, there remaines 660 paces. And forasmuch as the sayd peece eleuated at 20 grades, doth strike the marke 660 paces before the full end of the range of her bullet, it must of force pierce or batter sorer then the other peece whose bullet beates the marke but 140 paces be∣fore the full end of his range.