t find more extravagant when
applied, as I have indicated, with a glass rod, than one of 30 grains to
the ounce when the paper is floated, because in the former case I use only
just enough to cover the paper, viz. forty-five minims to a half-sheet of
{549} Canson's paper, and there is no loss from any portion adhering to the
dishes, evaporation, or filtering. This is far more than would be imagined
when only a sheet or two of paper is required at one time. Lastly, with
regard to the _strokes_ being visible after printing the positive, I do not
find them so in general, though occasionally such a thing does happen when
sufficient care has not been taken in the preparation; but I find striae
quite as visible on two positives prepared by DR. DIAMOND himself, which he
kindly gave me: however, I will forward a sample of my paper for your
judgment, and also a portion for K. N. M. if he will take the trouble of
trying the same.

GEO. SHADBOLT.

_New Developing Mixture._--Having for some months past used the following
developing mixture, and finding it very bright and easily applied, I beg to
offer it to your notice. It does not cost more than three farthings per
ounce, and therefore may be worth the consideration of beginners. I do not
know a better where the metallic appearance is not desired.

No. 1. Pyrogallic acid 2 grains.
Glacial acetic acid 1 drachm.
Water 1 oz.

No. 2. Protosulphate of iron 10 grains.
Nitric acid 2 drops.
Water 1 oz.

To six drachms of No. 2. add two of No. 1.

I pour it on, but do not return it to the bottle, as it is apt to spoil if
so used.

T. L. MERRITT.

_Queries on the Albumenized Process._--Allow me to put a few questions
through your valued paper.

In the albumen process on glass, Messrs. Ross and Thomson, in
Thornthwaite's _Guide_, recommend 10 drops of sat. solution of iodized
potassa to each egg. Now is it meant _ten drops_, or _ten minims_? If the
former, a drop varies with the bottle and quantity of liquid in it; and ten
drops are nearly half the bulk of ten minims, generally speaking. Then as
to the egg: an egg in this country is only at most 6 [drachm]; in England
an egg appears twice as large.--Could you state the general bulk of an egg
in England, and to what quantity by bulk or weight of albumen the 10 drops
or minims are to be applied? When I say an egg is only 6 [drac