"
[Illustration: ELECTRIC LIGHTING IN PARIS IN 1844.]
In the _Journal of the Royal Institution_, vol. i. (1802), Davy
describes (p. 106) a few experiments made with the pile, and says:
"When, instead of metals, pieces of well calcined carbon were employed,
the spark was still larger and of a clear white."
On page 214 he describes and figures an apparatus for taking the
galvano-electric spark into fluid and aeriform substances. This
apparatus consisted of a glass tube open at the top, and having at the
side a tube through which passed a wire that terminated in a carbon.
Another wire, likewise terminating in carbon, traversed the bottom and
was cemented in a vertical position.
But all these indications are posterior to a letter printed in
_Nicholson's Journal_, in October, 1800, p. 150, and entitled:
"Additional Experiments on Galvanic Electricity in a Letter to Mr.
Nicholson." The letter is dated Dowry Square, Hotwells, September 22,
1800, and is signed by Humphry Davy, who at this epoch was assistant to
Dr.
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