Ohje^ pfopofed ; for hb=z ipp being reduced 
will bc~yfo -\-hh +h j^^^^^j.^ which is the Hiriz.ontd 
rang at 45 degrees, that would juft rekch the OhjeB^ and the 
Elevation requifite will be eafily had ; for dividing the fo 
found ^emi'farameter by the Horizontal dijlame given the, 
Quote into Radius will be the Tangent of the Elevati m fought. . 
This Rule may be of good ufe ta all Bomhardiers and Gunner Sj 
not only that they may uft no more Powder than is necelTa- 
ry, to caft their Bombs into the place affigned, but that they 
may fhoot with much more certainty, for that a fmall Error 
conrimitted in the Elevation the Biece^ will produce no fen- 
fible difference in the fall of the Shot : For which Reafons the 
French Engineers in their late Sieges have uied Morter-pieces 
inclined conftantly to the Elevation of 45,proportioning their 
Charge of Powder according to the diftanceof the Object they 
intend to ftrike on t\\t Horizon. 
And this is all that need to be faid concerning this Pro- 
blem^ of Shooting upon bights 2sA defcents. But i( 2i Geome- 
trical conftruftion thereof be required ; I thiuk I have one, 
that is aseafy as any can be expefted, which I deduce from 
the forgoing Analytical Solution^ viz. ~r^^^y~ ^ ^"^^f ""^'^ 
and tis this. Having made the right A^gle L D A, Tab.i. 
fg. 4. make D A, D F 1=1 /, or greateft Rang, D G =: ^ 
the Horizontal diltance, and D B D C—hj the Berfendicu- 
lar hight of the Ob]e^ \ and draw G B, and make DE=: 
thereto. Then with the Radius A C and center E fweep an 
Arch, which if the thing be pofTible, will Interfeft the line 
A D in H ; and the line D H being kid both waies from F 
will give the points K andL, to which draw the lines G L, 
GK; I fay the Angles LGD, KGD are the Elevations re- 
quired for hitting the Object B. But note that if B be below the 
Horizon, its defcent D C=D B muft be laid from A, fo as to 
have AC = toAD-f DC. Note likewife, that if in def- 
€ent$ D H be. greater than F and . fo K fall below D the 
Angle. 
