I shall put
on a pair of spectacles for the experiment, as there is an injurious
effect of the voltaic spark upon the eyes, if the action is continued; and
it is neither policy nor bravery to subject any organ to unnecessary
danger; and I want, at all events, to keep the full use of my eyes to the
end of the lecture.
You now see the action of the heat upon the piece of platinum--heat so
great as to break in pieces the plate on which the drops of metal fall.
You perceive, then, that we have sufficiently powerful sources of heat in
nature to deal with platinum. I have here an apparatus by which the same
thing can be shewn. Here is a piece of platinum, which is put into a
crucible of carbon made at the end of one pole of the battery, and you
will see the brilliant light that will be produced. There is our furnace,
and the platinum is rapidly getting heated; and now you perceive that it
is melted, and throwing off little particles. What a magnificent
philosophical instrument this is. When you look at the result, which is
lying upon the charcoal, you will see a beautifully fused piece of
platinum. It is now a fiery globule, with a surface so bright, and smooth,
and reflecting, that I cannot tell whether it is transparent, or opaque,
or what.
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