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MINUTES OF PROCEEDINGS OF 
the 1858 -pattern shells this remedy was adopted. The arrangement, there¬ 
fore, by which the bursting of the shell is accomplished without the flight of 
the bullets being affected consists in the four grooves, and in the tendency 
to fracture round the line of junction of the Diaphragm being diminished to 
such an extent that the grooves are actually lines of least resistance. 
It is not necessary to dwell upon the other details and peculiarities of 
construction of these shells,—such as the coating of the interior with marine 
glue, the hardening of the balls with antimony, the introduction of coal dust 
between the bullets, the socket, the “ loading 99 hole, &c., all these details 
being more or less subordinate to one or other of the two main features 
which I have spoken of; and although they severally contribute to increase 
the general efficiency of the shells they are not connected with the particular 
objections which have been urged against the shells, and which in a succeed¬ 
ing paper I propose to discuss. 
The points which the present paper is intended to throw out into relief, 
and clearly establish, are as follows :— 
(1) That the efficiency of the original Shrapnel shell was impaired to such 
a degree by its liability to explode prematurely, as to make imperative the 
adoption of a remedy by which the defect would be overcome. 
(2) That the defect was proved by the most conclusive experiments to 
have been due in the vast majority of cases to the bursting charge being 
ignited by the percussion or friction of the bullets. 
(3) That the only efficient remedy for this defect was that proposed by 
Colonel Boxer,—the complete separation of the bursting charge from the 
bullets. 
(4) That Colonel Boxer proposed effecting this separation by means of an 
iron “ diaphragm.” 
(5) That this arrangement proved so efficient a remedy for the defect in 
question as to lead to its official recommendation and adoption ; a make-shift 
arrangement, confessedly imperfect, being applied to the existing store of 
Shrapnel shell. 
(6) That not only was the defect of premature explosion overcome in the 
Diaphragm shell, but the efficiency of the shell in another important point 
—the preservation of the bullets from the action of the bursting charge— 
was carefully secured by the peculiar distribution of the metal which was 
adopted. 
(7) That the details of this arrangement were not perfected until 1858; 
and therefore that the efficiency of this arrangement cannot be tested except 
with shells of the 1858 pattern. 
These points once established—once clearly grasped and their bearing 
fully appreciated—the question is disembarrassed of much superflous matter, 
and presents Itself narrowed down to a sufficiently fine issue. The Old and 
“ Improved 99 Shrapnel shell disappear,—with these we need concern our¬ 
selves no longer; we have now only to deal with shells of the Diaphragm 
construction, and with the objections which have been urged against that 
particular projectile. This is the subject which I propose to discuss in my 
next and concluding paper on Shrapnel Shells. 
