From some recent experiments of the Baron von Reichenbach, it seems
probable that wherever chemical action is going on light is evolved,
though it is only by persons possessing peculiar (though not very rare)
powers of sight, and by them only under peculiar circumstances, that it
can be seen. It occurred to him that such persons might perhaps see
light over graves in which dead bodies were undergoing decomposition. He
says:
"The desire to inflict a mortal wound on the monster,
superstition, which, from a similar origin, a few centuries ago,
inflicted on European society so vast an amount of misery; and by
whose influence, not hundreds, but thousands of innocent persons
died in tortures on the rack and at the stake;--this desire made
me wish to make the experiment, if possible, of bringing a highly
sensitive person, by night, to a churchyard."--§ 158. Gregory's
Translation, p. 126.
The experiment succeeded. Light "was chiefly seen over all new graves;
while there was no appearance of it over very old ones." The fact was
confirmed in subsequent experiments by five other sensitive persons, and
I have no design of questioning it. My doubt is only how far we can
consider the knowledge of it as giving a "mortal wound" to superstition.
"Thousands of ghost stories," the Baron tells us, "will now receive a
natural explanation, and will thus cease to be marvellous;" and he
afterwards says, "Thus I have, I trust, succeeded in tearing down one of
the densest veils of darkened ignorance and human error." I repeat that
I do not question the fact; my Query is, where to find the "thousands of
ghost stories" which are explained by it; and as I suspect that you have
some correspondents capable of giving information on such subjects, I
shall feel much obliged if they will tell me.