_Clouds in Photographs._--I wish one of your photographic correspondents
would inform me, how _clouds_ can be put into photographs taken on paper?
Mr. Buckle's photographs all contain _clouds_?
[Sigma].
"_The Stereoscope considered in relation to the Philosophy of Binocular
Vision_" is the title of a small pamphlet written by a frequent contributor
to this journal, Mr. C. MANSFIELD INGLEBY, in which he has "attempted to
sketch out such modifications of the theory of double vision as appear to
him to be entailed on the rationale of the stereoscope." The corroboration
thus indirectly afforded to the principles of Sir William Hamilton's
_Philosophy of Perception_ has induced MR. INGLEBY to dedicate his word to
that distinguished metaphysician. The essay will, we have no doubt, be
perused with great interest by many of our photographic friends, for whose
gratification we shall borrow its concluding paragraph.
"In conclusion we must not forget to acknowledge our obligations to the
photographic art, not merely as one of the most suggestive results of
natural science, but as a means of the widest and soundest utility. To
antiquaries the services of photography have a unique value, for, by
perpetuating in the form of negatives those monuments of nature and art
which, though exempt from common accident, are still subject to gradual
decay from time, it places in the hands of us all microscopically exact
antitypes of objects which, from change or distance, are otherwise
inaccessible. To the artist they afford the means of facilitating the
otherwise laborious, and often mechanical, task of drawing in detail
from nature and from the human figure.
"To the physician, to the naturalist, and to the man of science, the
uses of photography are various and important, and already the
discoveries which have been directly due to this modern art are of
stupendous utility.
"To the metaphysician, its uses may be sufficiently gleaned from the
applications considered in the preceding pages. But to all these
classes of men the photographic art derives its chief glory from its
application to the stereoscope; and if, for elucidating the principles
of vision by means of this application, we have in any degree given a
stimulus to the practice and improvement of the photographic processes,
our pains have been happily and fruitfully bestowed."
_Muller's Processes._--Would you inform me, through the medium of "N. &
Q.," what manufacture of paper is best adapted to the two processes of Mr.
Muller? I have tried several: with some I find that the combination of
their starch with the iodide of iron causes a dark precipitate upon the
face of the paper; and with those papers prepared with size, there appears
to me great difficulty (in his improved process after the paper is
moistened with aceto-nitrate of silver) to procure an equal distribution of
the iodide over its surface, as it invariably dries or runs off parts of
the paper, or is repelled by spots of size on the paper when dipped in the
iodide of iron bath.--A reply to the foregoing question would greatly
oblige