436 
Cast Steel* 
Stodart assures me that he has found the spring or elas- 
ticity of the steel to be greatly impaired by taking off the 
blue with sand paper or otherwise ; and, what is still more 
striking, that it may be restored again by the bluing pro- 
cess without any previous hardening or other additional 
treatment. 
Mr. Hardy, who is meritoriously known as a skilful 
artist, assured me some time ago that the saw- makers 
first harden their plates in the usual manner, in which 
state they are more or less contorted or warped, and are 
brittle that they then blaze them ; which process de- 
prives them of all springiness, so that they may be bend- 
ed and hammered quite flat, which is a delicate part of the 
art of saw making and that they blue them on an hot 
iron which renders them stiff* and springy without altering 
the flatness of their surface. Mr. H. finds that soft, un- 
hardened steel, may be rendered more elastic by bluing* 
and that hard steel is more expansible by heat than soft. 
It is very difficult to reason or even to conjecture upon 
these facts. They certainly deserve to be verified by a 
direct process of examination. 12 Nich. Jour. 63. 
Observations and experiments on steel , resembling that of 
Damascus ; with an easy test for determining the uni- 
form quality of steel before it is employed in works of 
delicacy or expence . 
In the infancy of society the hardest bodies, such as 
stones, and certain kinds of wood, were selected and used 
for cutting instruments, and still are applied to that pur- 
pose in several parts of the world. These materials were 
succeeded by copper, hardened by a mixture of tin, of 
which numerous weapons yet remain in the cabinets 
of the curious. And lastly, steel, whether obtained di- 
rectly from the ore, or by cementation of malleable iron, 
has deservedly taken place of every other article, on a u 
