A Manual Of Photography

ON THE APPLICATION OF THE DAGUERREOTYPE TO PAPER. 93 antimony and hydrochloric acid: in a few minutes it will become of an iron-brown colour, having a fine metallic lustre. It is again to be passed though a solution of silver, somewhat stronger than the first, and dried, taking care that no shadow falls on the paper whilst it is drying. It is then a second tone sub- mitted to sulphuration, and, by careful management, the process is now generally completed. If, however, the paper is not considered to be sufficiently dark, it must be once more washed in the solution of silver, and again subjected to the action of sulphuretted hydrogen. . . If the above paper be allowed to remain in the sulphuretted hydrogen gas after the maximum blackness is produced, it is again whitened with some quickness. This may be accounted for hi two ways: the gas may be mixed with a portion of muriatic acid vapour, or a quantity of chlorine sufficient to pro- duce this effect may be liberated from the preparation on the paper to react on the sulphuret of silver. . black The perfection of these papers consists in having ground to contrast with the mercurial deposit, by which means the pictures have the advantage of being seen equally well in all positions, whereas Daguerre’s pictures on the metal plates can only be seen to advantage at certain angles. ... - The sulphuretted paper may be rendered sensitive in the same manner as the plates by exposure to the vapour oiodinm I, however, prefer drawing the paper over & solution thu formed:—A saturated solution of any hydrioche salt is made to dissolve as much iodine as possible, and of this H^dt^ drachms are mingled with four ounces of water Care is re- quired that one side only of the paper is wetted, which is by no means difficult to effect, the fluid is so greedily absorbed by it all that is necessary being a broad shallow vessel to allow o the paper touching the fluid to its full width, and that it be KPovcr it wäh a slow steady movement. When thus wetted, it is to he quickly dried by a warm, but not .too b„ fire - of course daylight must be carefully excluded. r pe thus iodidated do not lose their sensitiveness for many days if v kept/ from li^kt- On exam ning the sheet after the daguerreotype processes in ii,, "„.,., .„.d of mercurialisation, have been completed, a very Wpt'e is found upon it: but it is still capable of vast mnrovpment which is, by the following simple plan, accom- nhshed Lawal which s once magical and beautiful. ^à,ILL« snimmatc-Dip one of the daguerreo- tvne nictures formed on the sulphuretted paper, into a solution of corrosive sublimate : the drawing instantly disappears, but,