168 
SHORT NOTES ON PROFESSIONAL SUBJECTS. 
The head of the body is pierced to receive the safety pin; the lead plug serves to 
close the hole left when the safety pin is withdrawn. The safety pin is prevented 
from dropping out by twisting the ends of its wire outwards, as shown in the engraving. 
The hole at this end of the pin is covered by a strip of metal, soldered on. A loop 
of cord is attached to the safety pin, in order that it may be withdrawn easily. A 
needle point is fixed in the centre of the head, above the cap in the pellet. 
The guard is a gun-metal collar, having two holes through which the safety pin 
passes, so as to keep it in position. 
The pellet has a cap fixed in its head containing a large charge of cap composi¬ 
tion (fulminate of mercury, sulphide of antimony, and chlorate of potash), protected 
by a very thin piece of sheet brass. On the exterior of the pellet are two projecting 
feathers, on which the guard is supported when the safety pin is withdrawn. 
The bottom plug screws into the body, and has a central hole, closed by a thin 
brass disc. 
The fuze is screwed into the shell by the G-.S. key, which fits into the slot in the 
head. The safety pin is withdrawn just before the shell is placed in the bore of a 
13.L. gun, and in the case of a M.L. gun when the shell is placed in the bore. 
Action .—On the shock of discharge the guard sets back, shearing otf the two 
feathers, and fastens on to the pellet, the metal of the latter expanding into the 
undercut recess shewn in the guard. The lead plug prevents the flash of the dis¬ 
charge from entering the fuze through the safety pin hole. On graze or on impact— 
as the case may be—the pellet and collar fly forward, the cap is exploded by 
striking against the needle point, and the flash from cap blows out the disc closing 
the bottom plug, and explodes the shell. 
107. Fuze, Time, Wood, ll.M.L. Ordnance. 
(Communicated by Captain J. Sladen, E.A.) 
Mark III. will be sealed for future manufacture, differing from II. in the head 
projecting farther from the shell, in having a larger groove containing more 
priming, and in having a copper band. The paper lining will be reduced in thick¬ 
ness, and the powder channels will be so placed as to be midway between the com¬ 
position channel and exterior, and reduced 1 in. in length. 
This pattern is found more certain or ignition than Mark II., and is also less 
liable to cause prematures with heavy charges, owing to the powder channels being- 
well protected. 
