398 
7 e ITALIAN FIELD GUIs. 
5 ft. 2 ins. to say 4 ft. 2 ins. It need not be explained here bow greatly 
tbis alteration would at once reduce tbe weight, not only of tbe wheels 
but of tbe body of tbe carriages themselves. It may be remarked that 
with tbe Italian guns no inconvenience is found in serving a gun of 
4 ft. 5 ins. between tbe wheels. It may be’ said too that it would be 
absurd to put teams of the colossal horses of England to draw carriages 
with wheels only 4 ft. in diameter; that tbe angle of tbe shaft would 
be practically bad—for a great deal of tbe force of tbe wheelers would 
be expended in lifting tbe wheels of tbe limber off tbe ground, as may 
be shown by decomposing tbe tractive force vertically and horizontally. 
That objection would be perfectly fair, but it is an objection tbe flank 
of which may be turned. It is not quite impossible, with a little inge¬ 
nuity and good will, to increase tbe curve of tbe end of tbe outside shaft, 
near its point of attachment to the axle. As to tbe inside shaft, it 
might be attached over tbe frame of tbe limber, while tbe splinter-bar 
might be raised to tbe same height as at present, to prevent kicks 
over. 
In tbe Italian artillery, tbe height of tbe axis of the trunnions is 
41 \ ins. above tbe plane—being very closely tbe height in tbe British 
field artillery. Tbe radius of their wheel is 24*8 ins., leaving a vertical 
distance between the axis of the trunnions and tbe centre of the axis of 
the two wheels, of close upon 16J ins. The writer of this paper, with 
all due deference to the designer, considers this to be a great defect ;* 
it quite unnecessarily raises the centre of gravity of the gun and 
carriage taken together, and gives rise to upsetting. It is no 'great 
palliation of the defect to say that the gun and carriage are so light 
that if they do upset they are easily righted. Further, it is objection¬ 
able in another way. If a line be drawn from the axis of the trunnions 
to the point of support of the trail on the ground, it will be found that 
its inclination to the horizontal plane is close upon 45°—nearly double 
that in the British service. This angle is intimately connected with 
the “jump” in firing, and it may be presumed that this “jump” 
with the 7 C gun is unusually great—a matter of no great importance, 
perhaps, provided that it is regular in amount, and that the carriage 
does not capsize over backwards when the recoil of the end of the trail 
is checked purposely or by accident. Such a construction would cer¬ 
tainly not suit a gun destined for the very high velocities lately 
introduced abroad. 
To continue, then, the subject of the effect of the reduction of the 
diameter of the wheel to 4 ft. If we were to retain the same trail- 
angle as at present of 22° or 23°, the length of the trail might be 
reduced in the direct ratio of the diameters of the existing wheel of 
5 ft. and the reduced wheel of 4 ft. j that is, the length of trail might 
be reduced by one-fifth. A notable gain in lightness and length of 
ground covered by the carriage would be the result. 
Thus, the more the subject is examined the clearer will it be proved 
^ The defect is recognised by Italian artillery officers: but the existing height of the axis of the 
gun is thought to be necessary in a country like Italy, where the plains are covered with such tall 
crops as maize, &c. 
