sefully in the preparation of slides for the magic
lantern?

Good slides are always expensive, owing, in great measure, to the accuracy
required, where every defect will be magnified some hundred times.

I would suggest that a photographic picture should be taken on the glass
plate, and then varnished. The painter should then apply his colours to the
_opposite_ side of the glass, using the photographic image as his outline.
The colours would then be burnt in, and the varnish and collodion film
cleared off.

This plan would be especially useful when the photographic picture had been
taken by the microscope.

THOS. SCOTT, B.A.

Brighton.

_Albumenized Paper._--If MR. HELE will follow the directions contained in a
paper of mine which you published in Vol. ix., p. 206., for albumenizing
paper, I think he will have no reason to complain of waves, or streaks, or
blotches, and will be saved the trouble of the damping process which he
uses and recommends to others. ("N. & Q.," Vol. ix., p. 254.) I have done a
considerable quantity of paper of Canson, both positive and negative, and
also of other makers, Whatman, Turner, Sandford, and Nash, and in all I
have succeeded perfectly in obtaining an even coating of albumen. I am
convinced from my own experience that the cause of waviness, &c., is due to
raising the paper from the albumen _too slowly_. If the paper be snatched
hastily from the solution, air bubbles no doubt will be formed; but if the
paper be raised with a steady even motion, _not too slow_, the albumen will
flow evenly from the paper, and it will dry with a perfectly even surface.

MR. SHADBOLT is certainly mistaken in saying that positives printed from
negatives will not stand a saturated solution of hypo. soda, unless they be
printed so intensely dark that all traces of a picture by reflected light
are obliterated. I have used nothing but a saturated solution for fixing my
positives for a considerable time, and my experience agrees with that of
other of your correspondents, that the picture is not as much reduced by a
saturated solution as by a weaker one. By adding about one grain of sel
d'or to every eight ounces of saturated solution, very rich black tones
will be obtained.

I inclose a specimen of what I have got in this way.

C. E. F.

[The specimen sent is most satisfactory; we wish that the locality of
the view had been stated.--ED.]

_Mounting Positives on Cardboard._--In the absence of