jan. — mar. 1857.] Pohtographic Printing Process. 167 



300 grs. Muriate of Ammonia, 

 240 grs. Sugar-candy. 



Float the paper on this for half a minute. Hang up and dry — 

 Ironing this paper before sensitizing seems quite unnecessary. 



To sensitize use, 



60 grains Nitrate of Silver, 

 12 minims Acetic Acid, 

 1 oz. Dist. Water. 



Float it on this for 4 or 5 minutes — hang up to dry. 



Expose in the pressure frame until the lights are a shade or two 

 darker than they ought to be in the finished picture. When print- 

 ed sufficiently — wash ail traces of the aceto-nitrate out of the 

 paper — in a darkened room. Dissolve off the Albuminate of Sil- 

 ver in a bath of Hyp. 1 to 8 of water, or of liquor Amm. 1 drachm 

 to 1 pint of water, in the former about 8 minutes — in the latter the 

 action is more violent and practice only will enable the operator to 

 judge of the time. 



The Print must be well washed after this bath and then immers- 

 ed in the toning bath composed of 



10 grains Chloride of Gold, 

 30 oz. Distilled water, 

 30 grains Hyposulph. Soda, 



30 minims of Hydrochloric acid if the chloride of Gold 

 be neutral. 



Mix the Gold and the Hypo, each in 15 oz. of water, and pour 

 the former into the latter gradually stirring the white. Then add 

 the acid if necessary. 



Keep the picture in this, till the shades are a deep purple, and 

 the lights, a pleasing grey. Then pass through water — (not for 

 more than a minute or two as the lights are yellowed by longer 

 washing,) into the second fixing bath of Hypo. I to 8 of water to 

 ensure its. perfect fixation. It should remain in this from ten to 

 fifteen minutes. Wash as usual. 



