141 
to Determine the Eifects of Different Modes of Treatment on 
Cast Iron for the Manufacture of Cannon.” 
After commenting upon the importance of the treatment of 
iron in the manufacture of cannon, and on the want of know'- 
ledge upon this subject, exhibited in the failure of many of the 
guns employed in the Russian War, the Author proceeds 
to describe the processes usually adopted in the foundry for 
the improvement of iron, under the heads mixing, re- 
melting, and prolonged fusion. The value of remelting 
and mixing iron has long been recognised, and their effect in 
increasing the tenacity of the metal has been fully demon- 
strated by experiments. Lately the influence of prolonged 
fusion had also been the subject of inquiry, and the conclusion 
had been arrived at that a continued exposure of liquid iron, 
to an intense heat, augments the cohesive powers of the iron 
in proportion to tin? duration of the exposure, up to some not 
well ascertained limit where the opposite effect begins to be 
produced, and the iron deteriorates. 
The Author then proceeds to narrate the results of some 
experiments in which he was engaged in 1855, on the 
improvement of cast iron ordnance. Five twenty-four pounder 
guns were cast of a carefully selected mixture of the following 
qualities of iron. 
Blaenavon, No. 1 
Blaenavon, No. 2 
Blaenavon, No. 3 
Lilleshall, No. 2 
Pontypool, No. 3 
. 2.2 
,16.7 
28.9 
35.5 
16.7 
per cent. 
55 
55 
15 
55 
In casting these guns it was sought to determine the effect 
of various modes of treatment in the foundry : hence, 
Gun A was cast in the usual w'ay, with 3 feet 0 inches head. 
Gun B was cast from the air furnace, of iron remclted 
once before casting into the mould. 
Gun C \vas cast from the ciq>ola, with desulphurized coke. 
