144 
MINUTES OF PROCEEDINGS OF 
r = —p-^'-- 8 - + (W+TF') sin e 
( e = 6J°) P = ~<ji 6 + 447'3664 
= 448*7187, or with a team of 6 horses 74*7864 lbs. per horse. 
In tlie 16-pr. M.L.R. gun-carriage with limber, Mark II. (packed), 
W — 36651bs. and W — 1000 lbs.; therefore, under the same circum¬ 
stances, 
P = 
50*8482 
” 80 
+ 528*0780 
=5 529*77291bs. } orwitha team of 6 horses 88*2955 lbs. per horse: 
and with a team of 8 horses 66*2216 lbs. per horse. 
That is, the traction of the 16-pr. gun-carriage is to that of the 9-pr. 
as 1*18 : 1. 
In the foregoing remarks the traction has been considered as applied 
at the axle, its particular point of application there being determined 
by the equation CE — ^ ^ . AC (see " Proceedings, R.A. Institution,” 
Yol. VIII. p. 371), where CE is the vertical distance of the point 
below the centre of the axle, and AC the radius of the latter, while 
P cos /3 , n ,v • 
sin 6 — ■ ._ - _ by (1 ). 
v/r + P-2P/f. sin/3 J ' 
In practice, the traction is usually from the splinter-bar; a conse¬ 
quence of which is that in a wagon fitted with frame shafts hinged to 
the bar a strain is thrown upon the connecting parts of the fore and 
hind carriages, and in a cart or limbered wagon with fixed shafts a 
pressure upon the shaft horse's back equal to P . where a and b are 
perpendiculars let fall from the point of application of P, when con¬ 
sidered as applied at the axle, respectively upon the direction of P 
applied at the splinter bar and upon the vertical drawn through the 
positions of the tugs on the shafts. 
In the 9 and 16-pr. limber, Mark II., neglecting the small distance 
CE —that is, taking the centre of the section of the axle-arm, at the 
shoulder, as the point of application of P when applied at the axle— 
the distance a = 8J ins. and b — 7 ft. 8 ins.; therefore ~ = *095. Or, to 
take particular cases, if P = 448*7187 lbs.—as in the example of the 
9-pr. gun-carriage above given—the pressure on the horse, due to the 
traction being from the splinter-bar, equals 42*628 lbs. ;* while if 
P = 529*7729 lbs.—as in the example of the 16-pr. gun-carriage—the 
pressure on the horse from the same cause equals 50*328 lbs.* 
Woolwich, 
December, 1874. 
* In addition to the constant pressure of about 60 lbs. due to bis bearing a portion of the weight 
of the carriage. 
