447 
THE 
CASTING- OF THE lOO-TON GUN 
iar the 
TURIN GUN FOUNDRY. 
{Translated from the " Italia Militare .”) 
CONTEIBUTED BY 
LIEUT.-GENERAL H. H. MAXWELL, C.B., R.A. 
On tlie morning of Wednesday, the 30th January, 1878, there was 
cast in the gun foundry of Turin a gun of a calibre of 45 cm (17'72-in.), 
which when finished will weigh 100 tons. The casting took place in the 
presence of the General Commanding the Division, General Bonelli, the 
General Commanding the District of Artillery, and General Rosset, the 
Director-General of Artillery, who proposed the gun and the method of 
its construction as far back as the 1st February, 1875. 
The casting, whether for its size, or still more for the limited means 
available for the work, is certainly one of the most important ever 
executed in Italy, and one the success of which assuredly does much 
honour to our artillery. We may, therefore, expend a few words in 
demonstration of the importance and difficulty of the work. 
The 100-ton gun under construction is of cast-iron, breech-loading, 
hooped with three concentric strata of steel rings, analogous to the 
24 and 32 cm (9*45 and 12‘20-in.) guns. Its total length is 10 metres 
(32*8 ft.), the calibre is 45 cm (17*72 ins.), the external diameter of the 
hooped part is 1*862 metre (5*92 ft.) It is to fire a projectile of about 
1000 kilogrammes (2205 lbs.) The cast-iron part of the gun—that 
which has just been run—will weigh, when finished, about one-half the 
weight of the finished gun. 
The system of casting adopted was that of Rodman, now in use for 
other guns of large calibre—that is, the siphon method, with a core 
cooled from the inside by cold water. The mould, of dry sand enclosed 
in keyed-up cast-iron boxes, was placed upright in a pit dug on 
purpose, and strutted up firmly therein. Three siphons of different 
lengths, opening into the mould tangentially, carried the metal in suc¬ 
cession into the mould from the channels immediately above them. 
Inside the core, made of a tube of wrought-iron covered with loam,, was 
the water-pipe. The mould measured 13 metres (42*7 ft.) in length 
over all; its internal cavity for the gun and deadhead was 12 metres 
