o be luminous hands there can
be no doubt. Whether he was deceived is another question.

As to the producing cause of these manifestations Professor Crooks
offers no theory. Whether the power and the intelligence displayed came
from some one present or from some disembodied spirit he makes no
suggestion, but simply presents the facts as evidence that there are
mysteries in nature transcending any that have yet been weighed and
measured, and which must engage the attention of the science of the
future.

Of the other scientists named, Professor Wallace openly accepts the
spiritualistic explanation of these phenomena. He has not, so far as we
are aware, published any detailed statement of his investigations,
though we have been told that they consisted in part in what is known as
"spirit photography," or the taking of photographs of persons known to
be dead, by his own private apparatus and in his own private rooms. As
to the character of the results obtained by him, however, we are unable
to make any statement.

Professor Zoellner also became a believer in Spiritualism, mainly through
experiments with the American medium Mr. Slade. He published a work on
the subject, in which he advances the theory, which has of late
attracted so much attention, of a fourth dimension in space; that is,
that, in addition to length, breadth, and thickness, bodies may have a
fourth dimension, beyond the powers of human observation. The untying of
knots in sealed ropes, passage of matter through matter, etc., he
attempts to explain as possibly done by agents capable of working in
this fourth dimension of matter. Science, however, is as little inclined
to accept this theory as to accept that of spirit communication.

Of the American scientific observers Professor Hare is far the most
noted for his critical discernment, his accuracy of observation, and his
obstinate determination not to be convinced that there was anything
occult in these phenomena. He was remarkably skilful in the making of
scientific apparatus, and he tested the phenomena received by a series
of instruments of delicate construction and capable of exposing the
least attempt at fraud. Those who were present at the circles with him
declare that he would frequently make his appearance with a new
instrument and a face full of grim expectancy that he would now baffle
the powers that had baffled him on previous occasions, and that he would
retire with a countenance of settled de