■H 
GUNPOWDER. 
TABLE II. For Projections on Ascents and Descents. Fig. 8, 9. 
7 
if. 
a 
y 
Given. 
Required. 
Proportions. 
i 
A M, A m, 
B m, A B, 
T A IF, 
t A H. 
A m : B m : : R : T. angle B A m, 
half of which added to 45°, ‘gives 
angle GAz. AM: AB::Ac: 
AC = CG. T. angle GAz: 
R : : G z : A z, and As — A f— 
f % =PG. 
C G : P G : : R : V. S. of S G,half 
of which added to, ortaken from 
GAz, gives the higher or lower 
direction required. 
2 
T A H, t A H, A F 
AM 
Log. of A M = Log. of A F x 2 
Log. S. angle MAF — Log. S. 
angle s A F — Log. S. angle 
M A s. 
3 
TA H, t AH, A M 
A F 
Log. of A F = Log. A M -f 
Log. S. angle s A F -j- Log. S. 
angle M A s — 2 Log. S. angle 
MAF, 
4 
BA m, t A H, A B, 
and any other angle 
t AH 
A b the amplitude for 
that other angle. 
Fig. 8. 
Log. Af = Log. A F -}- Log. 
S. angle jiA/-j- Log. S. angle 
p A M — Log. S. angle s A F 
— Log. S. angle MAi. 
5 
A M, D A H 
A? 
Fig. 5, e. 
T. angle GAz: Sec. angle 
g As: : Gz: Ag. 
1 
GUNPOWDER, a composition of nitre, 
sulphur, and charcoal, mixed together, and 
usually granulated. This easily takes fire, 
and when fired it rarefies or expands with 
great vehemence, by means of its elastic 
force. It is to this powder that we owe all 
the effect and action of guns, and ordnance 
of all sorts, so that fortification, with the mo- 
dern military art, &c, in a great measure 
depends upon it. 
The invention of gunpowder is ascribed 
by Polydore Virgil to a chemist, who hayi 
ing accidentally put some of his composi- 
tion in a mortar, and covered it with a 
stone, it happened to take fire, and blew 
up the stone. Thevet says, that the per- 
son here spoken of was a monk of Fri- 
bourg, named Constantine Anelzen; but 
Belleforet, and other authors, with more 
probability, hold it to be Bartholdus 
Schwartz, or the black, who discovered it, 
as some say, about the year 1320 ; and the 
first use of it is ascribed to the Venetians in 
file year 1380, during the war with the 
Genoese. But there are earlier accounts 
of its use, after the accident of Schwartz, as 
well as before it ; for Peter Mexia, in his 
“ Various Readings,” mentions that the 
Moors being besieged, in 1343, by Alphon- 
sus the Eleventh, King of Castile, discharged 
a kind of iron mortars upon them, which 
made a noise like thunder: and this is second- 
ed by what is related by Don Pedro, Bishop 
of Leon, in his Chronicle of King Alphon- 
sus, who reduced Toledo, viz. that in a sea 
combat between the King of Tunis, and 
the moorish King of Seville, about that 
time, those of Tunis had certain iron tubs 
or barrels, with which they threw thunder- 
bolts of fire. 
Pu Cange adds, that there is mention 
made of gunpowder in the registers of the 
chambers of accounts in France, as early 
as the year 1338. But it appears that Ro- 
ger Bacon knew of gunpowder near one 
hundred years before Schwartz was born ; 
and M. Dutens carries tire antiquity of 
gunpowder still much higher, and refers tu 
