303
march . 20 . 1678/9.
m
r. Henshaw the vice President tooke the chair.
The minutes of march the 13
th. were read which gaue occa
sion to Di
scour
se concerning the Ingredients of Gunpowder
m
r. Hooke conceiued that one great cau
se of the sudden Ex
pansion of the powders was the operation of the Alcalizate
salt in the Cole that serued to compound the powder
S
r. Iohn Hoskins doubted this
supposition conception querying
by w
t. meanes we were a
ssured of the being of Alcalj in Cole
And whether It could be thence extracted w
thout actually re
ducing it to a
shes. To w
ch. It was answered ^ /by m
r. Hooke/ that though pos
sibly It could not be actually extracted in the forme of an
alcalj salt, yet that it did produce its Effects as much as
if it were Reduced witne
sse the effects it hath vpon Iron
& copper to Reduce them into steel & Bra
sse. Besides that
the effect thereof seems manife
stly to be the very same w
th the
Alcalj in the Puluis Fulminans, which is made of niter
and sulphur in the same proportions as in Gunpowder
and Differs only from it, in hauing an alcalizate
salt -
mixed w
th the other ingredients in
steed of powder of charcole
And that the sudden expansion in each of them was occasioned by
the salts working one vpon the other in the way of Di
ssolution
that De
scartes Hypothesis of the turbinated motion of the nitrous
parts was not sufficient for the effect; nor was their any grou[nd]
to
suppose beleiue such a motion. S
r. Iohn Hoskins vrged that
as there was very little acalj to be extracted out of
cole a
small quantity of cole any way, and soe twas not likely to be the
cau
se of soe great an effect, soe that euen of that w
ch. was
a great part of it would be left behind after the Gunpowder
was fired in a musket Barrell or the like, soe that It should
Rather seem that the Alcalizate part were v
sele
sse & in
signifi
cant It being none of the parts
flew aw that expand & fly away
Ref: CELL/RS/HF_305 © Centre for Editing Lives and Letters