iations. Now, however,
after habituating myself to examine it with the same sort of strain
that one tries to decipher a signpost in the dark, I have found out
that this is by no means the case, but that a kaleidoscopic change
of patterns and forms is continually going on, but they are too
fugitive and elaborate for me to draw with any approach to truth. I
am astonished at their variety, and cannot guess in the remotest
degree the cause of them. They disappear out of sight and memory the
instant I begin to think about anything, and it is curious to me
that they should often be so certainly present and yet be habitually
overlooked. If they were more vivid, the case would be very different,
and it is most easily conceivable that some very slight
physiological change, short of a really morbid character, would
enhance their vividness. My own deficiencies, however, are well
supplied by other drawings in my possession. These are by the Rev.
George Henslow, whose visions are far more vivid than mine. His
experiences are not unlike those of Goethe, who said, in an
often-quoted passage, that whenever he bent his head and closed his
eyes and thought of a rose, a sort of rosette made its appearance,
which would not keep its shape steady for a moment, but unfolded
from within, throwing out a succession of petals, mostly red but
sometimes green, and that it continued to do so without change in
brightness and without causing him any fatigue so long as he cared to
watch it. Mr. Henslow, when he shuts his eyes and waits, is sure in
a short time to see before him the clear image of some object or
other, but usually not quite natural in its shape. It then begins to
change from one form to another, in his case also for as long a time
as he cares to watch it. Mr. Henslow has zealously made repeated
experiments on himself, and has drawn what he sees. He has also tried
how far he is able to mould the visions according to his will. In
one case, after much effort, he contrived to bring the imagery back
to its starting-point, and thereby to form what he terms a "visual
cycle." The following account is extracted and condensed from his
very interesting letter, and will explain the illustrations copied
from his drawings that are given in Plate IV.

Fig. 70. The first image that spontaneously presented itself was a
cross-bow (1); this was immediately provided with an arrow (2),
remarkable for its pronounced barb and superabundance of feathering.
S