PHOTOGRAPHY 
the cover, through the leaves to the front, and 
an end through each of the side perforations, 
then through the central loop, drawn tight and 
tied in a bow-knot. 
_ Blue prints can be made on fabrics almost as 
easily as on paper. The process is not expen- 
sive; the operations are simple, the results 
pleasing and permanent. The fabrics should 
be washed and stretched on light frames. When 
dry, they may be sensitized with equal parts of 
the following solutions applied with a tuft of 
cotton: 
a—Citrate of iron and ammonia... 160 grains 
PR ae owns acs ase & 1 ounce 
b—Red prussiate of pe =) ee 120 grains 
Wretero-<c..-3 = é 1 ounce 
These solutions should be kept separately in 
the dark, and mixed only as required for usé. 
The sensitized fabrics, when dry, should be 
printed immediately, preferably in sunlight, 
and until the shadows have a deep bronzed 
appearance. The development should be in 
clean water, and the fabrics washed in several 
changes of water until all yellowness is gone. 
When dry the fabrics may be ironed smooth. 
White goods are preferable for this process. 
The cream and yellows are inclined to give the 
blues a greenish cast. For pillow covers, mer- 
cerized sateen, butcher’s linen and some of the 
cambrics will be suitable. 

To Tone Bromide and Gaslight Prints 
The tones can be secured, on these papers, 
with possibilities of failure reduced to a mini- 
mum, by resorting to a subsequent toning 
process. The oldest is the uranium method, 
which we published in a previous number. 
This was followed by the hot hypo-alum bath, 
which after a short period of service was super- 
seded by the cold bath. The baths and the 
directions for using them are as follows: 
HOT HYPO-ALUM BATH 
PMNS. Ceatcins waprain ioe a diexaue > = # ounces 
2 quarts 
This bath should not be filtered and it 
will improve by keeping. 
It is advised that the prints, when fixed, be 
rinsed in three changes of water, thenimmersed 
in a strong solution of alum to harden the 
gelatine, washed and dried before toning. 
When ready to tone, immerse the prints in the 
cooled bath, set the tray containing it into 
another tray of hot water and raise the temper- 
ature of the bath to about 110 degrees Fahren- 
heit; keeping the prints separated from each 
other until the completion of the toning, which 
will require but a few minutes. 
To prepare this bath for cold toning it is 
only necessary to dilute its bulk with an equal 
quantity of water. The prints, after having 
473 
been washed in a few changes of water, can be 
immersed at once in the bath, and should be 
turned over and separated from one another 
occasionally. From twelve to twenty-four 
hours will be required to complete the toning. 
If the prints are taken from the fixing bath 
and, without washing, put in the toning bath, 
they are liable to bleach too much. Both hot 
and cold baths bleach the prints to a certain 
extent, so it is necessary to make the prints 
which are to be toned in either a little darker 
than is usual for prints that are to remain 
untoned. 
To tone by redevelopment there will be 
required three solutions, which are made as 
follows: ~* ; 
No. 
Ferricyanide of potassium (red prus- 
siate of potash) 5 drams 
UY Faced et ee oe hes bos ck on 12 ounces 
No. 2 
Bromide of potassium.............. 5 drams 
NID DIE epee See eee eee a 12 ounces 
f ; No. 3 
Sulphide’ef soduim ...24.<.<<--- 0.50 14 ounces 
Ee a ably dg la a am ae ee 12 ounces 
The prints, having been washed and dried, 
must be bleached in a bath composed of equal 
parts of No. 1, No. 2 and water, with the 
addition of one drop of concentrated ammonia 
to each two ounces of bath. After washing 
the prints should be redeveloped in a bath of 
one part of No. 3 diluted with eight parts of 
water. 
Sulphide of sodium being a very unstable 
salt, liquefying rapidly after having been 
exposed to the air and having the odor of strong 
sulphur water, it is advised that it be not used 
in a room where plates, paper or other sensitized 
goods are kept; its fumes might be injurious 
to them. Usually, we advise amateurs to 
compound their solutions, but we except the 
sodium sulphide redeveloper, especially where 
small lots or only occasional work is to be done. 
The redeveloper can be purchased in con- 
venient form, the ferricyanide and bromide 
being in capsules, needing only to be dissolved 
in the requisite quantity of water, and the 
sodium sulphide being in a_ concentrated 
solution. 

Correspondence 
Mr. A. T. Ross, Dixon, Cal., writes: ‘‘I 
have read so many articles on lenses and their 
focal length that I am now at a loss to select 
one. I have just read an article in which it 
was stated that the lens for a 5 x 7 plate should 
be ten to twelve inches focus, and in another 
article that the focal length of the lens should 
be the length of the plate. What are we 
amateurs to do when writers who claim toknow 
