TITE EOYAL ARTILLERY INSTITUTION. 
301 
The ends of the strands are then roughly wrapped round the head of 
the fuze, and lie in the exterior groove. 
The fuze is then placed in a die, head downwards, and compressed 
rings of fuze composition are forced over the spindle by hydraulic 
pressure, until the composition hollow is filled to within *25 in. of the 
end of the fuze, where the undercut on both the body and spindle has 
been made. This undercut groove is then tamped, as before mentioned. 
During* the preceding operation a steel former or drift remains in the 
powder channel of the spindle, and is now withdrawn. The fuze is then Priming, 
removed from the die, and mealed powder is shaken in through the fire- 
holes until they are full, when the strands of the quick-match are again 
re-wrapped round the head, and covered in by a band, as in the present 
service time fuze. 
Graduation and Marking. 
A spiral line of ’4 in. pitch is then marked on the exterior surface of Graduation, 
the fuze, commencing at the lower edge of the exterior groove. The 
exterior surface of the groove is also divided longitudinally into eight 
parts, by eight straight lines passing down the whole length of the fuze. 
The intersections which these lines make with the spiral thus mark off 
that spiral into spaces, each of which gives a difference of *05 in., and 
as each inch burns 5 seconds, each division will mark ’25 second. 
I have adopted this plan of marking the fuze into seconds and 
quarter seconds, as a knowledge of the time of flight for each range 
will be all that is required for boring the fuze. 
These divisions may be further subdivided by eye, where very great 
accuracy is required, as there is considerable space between each inter¬ 
section. 
Advantages. 
With reference to the advantages offered by this construction, a glance 
at the accompanying sketches will readily convince anyone that the 
objects mentioned under heads («), (b), (c), and ( cl ) are attained. 
This is not at first sight so evident with reference to (e) —viz., increased 
facility for testing the accuracy of the rate of burning. It is, however, 
to be attained in the following manner :— 
The brass disc at the bottom of the powder channel is removed, and 
the powder shaken out. The powder channel is then continued right 
through the fuze by prolonging it through the head. The lower end of 
the powder channel is then tamped with *25 in. of clay. A few grains 
of E.P.G. are inserted from the top, so as to fill up about ’5 in. of the 
channel, when a small plug of clay about ’1 in. thick is placed over it, 
and similar charges thus introduced at every half-inch of the powder 
channel until it is filled. If now holes be bored through the fuze to the 
powder channel—care being taken that no two holes are bored into the 
same charge—and the fuze be ignited, the times corresponding to the 
boring can be accurately noted, from each separate charge (as the com¬ 
position burns down to the place where it is bored) giving a distinct 
report. 
