At a recent meeting of the Royal Institution, there were exhibited some
specimens of paper manufactured from straw, by a new process.
_Hardening Steel_.
From the observation of travellers, that the manufacture of Damascus
blades was carried on only during the time when the north winds
occurred, M. Anozoff made experiments on the hardening of steel
instruments, by putting them, when heated, into a powerful current of
air, instead of quenching them in water. From the experiments already
made, he expects ultimate success. He finds that, for very sharp-edged
instruments, this method is much better than the ordinary one; that the
colder the air and the more rapid its stream, the greater is the effect.
The effect varies with the thickness of the mass to be hardened. The
method succeeds well with case-hardened goods.-- _From the French_.
_Detection of Blood_.
A controversy has recently taken place in Paris, relative to the
efficacy of certain chemical means of ascertaining whether dried spots
or stains of matter suspected to be blood, are or were blood, or not.
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