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soft, as success depends in a great measure on their pliabdity [ at this stage. The time that elapses while the mounted । prints are drying may be occupied in preparing the plates. Patent plate free from imperfections should be cleaned | with dilute nitric acid, well washed, and polished with tripoli, or any of the substances usually employed for plate cleaning; powdered French chalk (talc) is dusted on the sur face, and removed with the polishing cloth. Pass a camel- hair brush over the plates to remove any particles of dust, then coat them with normal collodion in the same manner as coating a wet plate or varnishing a negative ; when set, rear on end to dry. A. number of plates may be coated, as they will be none the worse for keeping. We will sup pose the mounted photographs have been soaked as directed, and are soft; remove them from the dish of water to a clean damp cloth ; blot off the excess of water, and leave them in the cloth until they are required for the next operation. The gelatine should be re-melted in a flat porcelain dish over a water bath ; into the solution immerse one of the dry collodion plates, and one of the photographs from the damp cloth. To bring these two into perfect contact requires a little skill and practice. From our description, however, it should not be found at all difficult. With the left hand hold the plate, collodion side uppermost, just under the surface of the solution; with the right hand lower the print gradually on to the plate, commencing at the bottom and working upwards. The top of the print should be held outwards, so as to form a slight curve ; by this means it will be easy to see the air-bells gradually pushed out as the two surfaces come in contact. Having accomplished this satisfactorily, lay the plate down on the bench, and well squeegee the back of the photograph to remove any excess of gelatine and air imprisonedin the paper. When all the prints have been squeegeed down on their respective plates, place them in a current of dry air, and leave them for twelve hours ; at the end of that period the prints will probably have dropped off the plates; if not, they will come away quite easily if the point of a penknife is passed round the outer edges to give them a start. It is not usual for photographers to deliver these so-called enamelled photographs to their clients in this condition; they are generally stamped up by an embossing press. The margin, after being reduced to the required size (prints intended for enamelling need not be cut until after they leave the glass plate), is fastened with glue to an ordinary thick card mount. When cabinet or larger sizes are produced, the air space between the em bossing and the ordinary mount should be filled with cotton wool padding, to prevent the centre falling in by reason of changes in the atmosphere. It will be seen that the highest degree of finish can be obtained by this method. Pictures printed as cameo vignettes, medallions, and cushion-shapes with priuted-in margin, as described in a former lesson, are particularly suited to this class of work. Fig. 3 is a sketch of an embossing press. The print is adjusted so that when the pressure is exerted the Fig. 3. metal die fits exactly over the mask line selected in printing ; that is to say, an oval used in printing should be of the same dimensions as the die of the embossing press. Do not apply too much pressure, and immediately remove the print, for unless the cardboard be of unusually good quality, it will in all probability burst. Many in experienced persons fall into error in this particular, and throw the blame on the pressor the cardboard. To avoid such failures, allow the print to remain under less pres sure for a longer period, say one or two minutes. Before quitting the subject of enamelling, it will be well to give directions for removing the white and other spots caused by dust in printing and imperfections in the nega tive. Water colours may be used for the purpose, pro vided the medium cannot be easily removed by water. Such a substance we have in spike oil of lavender. For white spots, mix India ink, Indian rod, and neutral tint with spike oil of lavender to the consistency of cream; test it for shade of colour by touching out a white spot. Use a sable brush with good point. Let the brush be charged freely with colour, and then worked nearly dry on the palette ; by adopting this measure, the beginner will soon be able to touch prints successfully, an achievement he would not attain if the brush were loaded with colour. In the latter case, he would take out a white spot, and put in a black one—a circumstance sometimes met with among professional spotters. If the colour is the same shade as the photograph, then proceed to remove all the white spots, levelling them carefully into the surrounding parts. Dark spots may be lightened with Chinese or zinc white and Indian red mixed with spike oil as before. All the working up that is intended to be put on the print should be done after mounting, and before soaking in the vessel of cold water Another vehicle is sometimes used for mixing the colours, viz., gelatine containing a small pro portion of chrome alum to render it insoluble. There are other methods of obtaining enamelled surfaces, differing from the foregoing, inasmuch as the vehicle gelatine is dispensed with in one, and both gelatine and collodion in another. In the former case, the glass plate is coated with wax in one of its solvents (either benzoline spirit, or methylated ether will do), over this the plate receives a film of plain collodion in which the solvents are about equally proportioned. Thus:— Pyroxyline (Hopkinand Williams) ounce Methylated alcohol ... .. 10 ounces ,, ether 10 » Castor oil 20 drops Moisten the cotton with 2 ounces of alcohol, then add the ether. Finally add the remaining 8 ounces of alcohol in which the castor oil has been previously dissolved. When set, it should be washed in cold water until, when water is poured on, streaks and greasy lines have dis appeared. Unmounted prints previously soaked in water are to be