I thank you for the experiments communicated. I sent immediately for
your brimstone globe, in order to make the trials you desired, but
found it wanted centres, which I have not time now to supply; but the
first leisure I will get it fitted for use, try the experiments, and
acquaint you with the result.
In the mean time I suspect, that the different attractions and
repulsions you observed, proceeded rather from the greater or smaller
quantities of the fire you obtained from different bodies, than from
its being of a different _kind_, or having a different _direction_.
In haste,