BtJKSTING OF HEAVY GUNS. 
191 
of strength forward—in fact, would be as well able to stand a charge 
fired half-way up as at the bottom of the bore. They could hardly 
be better made for this express experiment. If the 7-in. Woolwich 
gun is allowed to bear on service 30 lbs. of pebble powder and a 
160-lb. shot, the mere weight of powder and metal employed, even in 
the fifth round—namely, 36 lbs. of powder and 185 lbs. of shot— 
doubtless might be well borne. There remains still the violent and 
sudden action due to the position of the front charge between the 
two shot. This action I have said in the case of the 38-ton gun was 
apparently so violent as not to resemble the normal explosion of 
powder. This strain Sir W. PalliseEs gun, being a converted and old 
weapon, has borne wonderfully well, and deserves very high praise for 
it. The coils have been abundantly proved to be admirable. The 
question may perhaps be raised whether our present large cheap coils 
would stand as well. As the experiment stands, Sir W. Palliser has 
made out a good case for coiled inner tubes of iron; but it must not 
be forgotten that the analogy between large and small guns is com¬ 
paratively remote, and that both the projectiles used on this occasion 
were solid. 
4. The Keupp Gun Accident. 
The annexed illustrations are copies of rough sketches taken by 
Herr Krupp ; s engineer, sent to examine the remaining portions of the 
9-in. gun of 14 tons which recently burst on board the German 
training ship “Renown”—a vessel originally purchased from the 
English Government. The gun in question was manufactured in 
1868, and has been in use since 1870. It had received severe usage, 
and showed deep erosion or guttering about the position where it 
eventually yielded. One shell which burst in its bore had produced 
some injury, and it had been remarked upon as a gun which ought not 
to be fired again. Messrs. Krupp suggest that the probable cause of 
explosion was as follows :—It was loaded with a chilled projectile with 
a lead coat. Such projectiles are specially liable to have cracks 
developed in the chilled metal in the process of re-heating to take the 
lead coat. This projectile probably became ruptured in firing, and 
wedged in the portion in front of the trunnions. Hence the gun 
yielded, the front portion of the barrel being carried away with the 
projectile, the breech end blown to the rear, and the central portion 
with trunnion ring left on the carriage with the tubes in the opened 
condition shown by the dotted lines, which indicate the effect of a 
great longitudinal strain. It is to be observed that the gun only 
parted into these large fragments, the men who were killed and 
wounded being injured by the gas , not by actual impact of pieces of 
metal. 
If the gun bursts in a dangerous way and kills the men round it, it is 
a matter of comparatively small importance whether death is caused by 
gas or fragments of metal. The burst is to be admired from one point 
of view, inasmuch as the gun has certainly been subjected to a very 
great strain, and has yielded simultaneously in various ways—laterally, 
