lind."

"I have often heard that effect of the moon in the tropics mentioned,
but have never seen it. In what manner does it affect the eyes?"

"The moon can act but in one way, sir," replied Macallan,--"by
attraction. The men who are affected see perfectly well in broad
daylight; but as soon as it is dusk, their powers of vision are gone
altogether. At the usual time at which the hammocks are piped down they
will not be able to distinguish the numbers. I have had sixty men in
one ship in the situation I have described."

"We ridicule the opinion of the ancients, relative to the powers of this
planet," observed the captain; "but, at the same time, I have often
heard more ascribed to her influence than the world in general are
inclined to credit. That she regulates the tides is, I believe, the
only point upon which there is now no scepticism."

"There has been scepticism even upon that, sir. Did you ever read a
work entitled `Theory of the Tides'? I can, however, state some other
points, from observation, in which the moon has power."

"Over lunatics, I presume?"

"Most certainly; and why not, therefore, over those who are rational?
We observe the effect more clearly in the lunatic, because his mind is
in a state of feverish excitement; but if the moon can act upon the
diseased brain, it must also have power, although less perceptible, over
the mind which is in health. I believe that there is an ebb and flow of
power in our internal mechanism, corresponding to the phases of the
moon. I mean, that the blood flows more rapidly, and the powers of
nature are more stimulated, at the flood and full, than at the ebb and
neap, when a reaction takes place in proportion to the previous
acceleration. Dr Mead has observed, that of those who are at the point
of death, nine out of ten quit this world at the ebb of the tide. Does
not this observation suggest the idea, that nature has relaxed her
efforts during that period, after having been stimulated during the
flood? Shakespeare, who was a true observer of nature, has not omitted
this circumstance; speaking of the death of Falstaff, Mrs Quickly
observes, `It was just at the turn of the tide.'"

"Well, but, Mr Macallan, laying aside hypothesis, what have you
ascertained, from actual observation, besides that which we term
moon-blindness?"

"The effect of the moon upon fish, and other animal matter, hung up in
its rays at night. If under the half-deck, they would