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MINUTES OP PROCEEDINGS OP 
A gun was about to be made of this compressed bronze, when the 
Exhibition of Vienna took place, and amongst the war materiel there 
displayed, was to be seen a bronze gun, cast by M. Laveissiere, of Paris, 
in a thick cast iron mould, so as to be cooled very rapidly; the 
longitudinal section of this gun, showed a homogeneous metal quite 
free from the spots, while the tests applied to specimens by General 
Morin, left no doubt as to the great strength of the metal, which seemed 
to resemble very much in its qualities the compressed bronze before 
mentioned. 
This mode of manufacture, by casting in chill, being simpler than that 
of casting under pressure, it was resolved to adopt it in further 
experiment, and in August, 1873, a mass of bronze representing the 
breech end of a field gun was cast in an iron mould, five inches thick.* * * § 
The bronze solidified in about 5 minutes, contracting considerably, so 
as to leave a hollow in the middle of the casting. 
From the lower and more solid portion of the cylinder a disc was cut 
which showed towards the outer circumference, where the cooling had 
been most rapid, beautiful golden hued crystals, with their axes lying 
in a direction perpendicular to the surface of the cylinder, these crystals 
extended to a distance of P6 inches from the circumference, and 
gradually passed into a grey mass of very fine grains, which formed the 
central portion of the cylinder.f The properties of this crystalline 
portion are shown in table A. in the column headed “ Bronze cooled 
in metal mould they resemble the properties of bronze, cast under 
pressure and of the Laveissiere bronze. 
A great step had thus been taken in bronze manufacture, for this 
chilled bronze far surpassed that made in the common way in tenacity, 
though it had little advantage in elasticity and none at all in hardness, j 
A piece of this chilled bronze was next forged cold by rolling, 
considerable force was required, but the bar tested was extended by 
100%, or to double its original length, without showing the least fissure. 
When lengthened only 20°/ Q by the same process, the properties of this 
metal changed wonderfully, and it presented the same strength, hardness 
and elasticity as steel .—Vide table A. 
Column headed, “bronze (cast in chill), rolled. §” 
This then is the metal to which General Von Uchatius has given the 
name of “ bronze steel ” It will be seen how appropriate a name this 
is, when we consider the latest definition of steel itself, viz :—“ Any alloy 
or variety of iron, cast when in a melted state, into a malleable ingot.” 
* The bronze contained 10°/^ of tin 5 the dimensions of the mould were 28 inches in 
height and 10 inches in diameter 
# t This is more or less a characteristic of all bronze castings, the interior being always 
richer in tin, and presenting a different crystalline fracture from the exterior. 
I This property was tested by the depth of indent made by a knife, under a given stated 
pressure. 
§ The tensile strength of the metal was now 82 tons per square inch, and its limit of 
elasticity 11 tons. The tensile strength of Firth’s steel used in our own gun building is 
about 30 tons untempered, (about 50 tons when tempered), and its elastic limit about 
13 tons, while as shown by table A. Krupp’s gun steel has a tensile strength of over 30 tons, 
and an elastic limit of about 6 tons. 
