hours
after leaving them, and he had been led, with some success, as he
alleged, to investigate the cause. It appeared to him "that the strong
vivid light evolved from the numerous gas-lamps on the stage so
powerfully stimulated the brain through the medium of the optic
nerves, as to occasion a preternatural determination of blood to the
head, capable of producing headache or giddiness: and if the subject
should at the time laugh heartily, the additional influx of blood
which takes place, may rupture a vessel, the consequence of which will
be, from the effusion of blood within the substance of the brain, or
on its surface, fatal apoplexy." From inquiries he had made among his
professional brethren who had been many years in practice in the
Metropolis, it appeared to him that the votaries of the drama were by
no means so subject to apoplexy or nervous headache _before_ the
adoption of gas-lights. Some of his medical friends were of opinion
that the air of the theatre was very considerably deteriorated by the
combustion of gas, and that the consumption of oxygen, and the new
products, and the escape of hydrogen, occasioned congestion of the
vessels of the head. He thought it probable that this deterioration
of the air might act in conjunction with the vivid light in producing
either apoplexy or nervous headache. He found, moreover, that the
actors were subject not only to headache, but also to weakness of
sight and attacks of giddiness, from the action of the powerfully
vivid light evolved from the combustion of gas; and he noted that the
pupils of the eyes of all actors or actresses, who had been two or
three years on the stage, were much dilated; though this, he thought,
might be attributable to the injurious pigments they employed to
heighten their complexions; common rouge containing either red oxide
of lead or the sulphuret of mercury, and white paint being often
composed of carbonate of lead, all of which were capable of acting
detrimentally upon the optic nerve.

The statements of "Chiro-Medicus" may seem somewhat overcharged; yet,
after allowance has been made for that exaggerated way of putting the
case which seems habitual to "the faculty" when it takes up with a new
theory, a sufficient residuum of fact remains to justify many of the
doctor's remarks. That a headache too often follows hard upon a
dramatic entertainment must be tolerably plain to anyone who has ever
sat in a theatre. Surely a better state of t