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minutes OF PROCEEDINGS OF 
but this was found to strain the gun too much, and the Ordnance Select 
Committee thoroughly investigated the matter, and having obtained the 
particulars of proof of guns in Prance, Belgium, Holland, Austria, Spain, 
Saxony, Denmark, America, Wurtemberg, Bavaria, and Sweden, came to the 
conclusion that the proof should be based on the highest charge which the 
gun will have to bear on service, and recommended the present proportionate 
charge for rifled M.L. guns, which was approved 13th July, 1864. 
After proof, water is force-pumped into the bore, with the pressure of 
120 lbs. to the square inch. This was instituted for guns with wrought- 
iron barrels to ascertain that the breech was perfectly closed, and is still 
continued in the case of solid-ended steel barrels, to make sure that the end 
has not been split in proof. After this the gun is cleaned, and gutta percha 
impressions of the bore being taken as before, the two sets of impressions 
are compared, to ascertain that no flaw of a serious character has been 
developed by proof. If any defect appears of which there is even the 
slightest doubt, the gun is subjected to five more rounds with service 
charges, and if after that the flaw does not appear to have increased, the 
gun is passed. 
Processes after Proof and before Issue. 
(1) Lapping. 
(2) Obtaining preponderance and weight. 
(3) Lining. 
(4) Sighting. 
(5) Venting. 
(6) Marking, and the “marks ” denoting pattern. 
(7) Fixing on elevating plates and small fittings, sloping sides of cascable, and 
scoring breech. 
(8) Painting and lacquering, and final inspection. 
All the above processes except the last are performed in the one workshop 
(the sighting room), and generally, but not necessarily, in the exact order 
given. 
(1) Every gun is lapped after proof, for the purpose of removing any 
little burs which may be thrown up on the edges of the grooves by the 
impetuous proof rounds. 
(2) The meaning of the term “ preponderance" as applied to modern guns, 
is the pressure which the breech portion of the gun, when horizontal, exerts 
on the elevating arrangement. 
To ascertain the preponderance, the gun is supported at the trunnions by 
steel bars placed beneath them, and is brought horizontal by means of long 
handspikes in the bore. A Kitchen's weighing machine (like that ordinarily 
used at railways for weighing luggage), is then placed under the breech, and 
a block of wood is fixed on it, touching the gun underneath mid way between 
the elevating points. The handspikes being then removed from the bore, 
the pressure on the block is indicated on the arm of the machine, and is the 
preponderance of the gun. 
The preponderance of heavy guns should be as small as possible, so as 
not to interfere with the easy action of the elevating arrangement. 5 cwt. 
was assigned for 9-inch guns, and between 5 and 6 cwt. for the heavier guns; 
but by a recent order, 13th April 1869, all sea-service guns of 18 tons and 
