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of the Habessines. the which was Read, and orderd to be
kept in the Library and thanks returnd to the sender

Mr. Perkins Presented a Paper conteining 3 querys about
the mixture of mettalls.

The first was. A Piece of Gold not being malleable calld Eager what
is the way to toughen it & make it malleable wth.out aqua fortis

Mr. Henshaw conceiud the best way would be to anneale it
by degrees for that . . . . metalls being and Glasse being suddenly
Quenched or cooled would become brittle

Mr. Hooke sayd there was a way of making some mixtures of
metalls (as the factitious Gold made wth spelter) which is of its
self very brittle) very tough & malleable by cementing it
wth. a vegetable powder, he also mentiond that there was a
way of hardening an amalgam of mercury & Iron by a vegetable
powder which would make it almost as hard as hardned steel.
this he conceiud would be an excellent materiall for making
Specular plates for telescopes in Mr. Newtons way for that
the form of such plates would be easily giuen by laying
the said amalgam when soft vpon the conuex side of an
obiect Glasse for a telescope made very large. the
composition & manner of making & hardning that Amalga
was much Desired.

Mr. Hooke said he had been Lately told of a way to harden
. . . . . . . and fix mercury but he had not yet tryed it
to see whether it Did succeed.

Ref: CELL/RS/HF_440  © Centre for Editing Lives and Letters