=Stripping the Collodion Film= is a safe and cheap procedure for producing the necessary reversal, and in the subsequent printing operations the danger of breakage, when compared with glass, is reduced to a minimum. The glass plate, free from defects, must be well cleaned, and it is safer, and renders the stripping more certain, if it be covered with a fine film of pure beeswax. This is best applied by rubbing over the surface a few drops of a solution of beeswax in benzole and carefully polishing, at the same time avoiding the entire removal of the wax. The piece of linen used in the operation should be rubbed upon a lump of wax previous to the polishing. The plate must on no account be gelatinised or albumenised, except round the edge only, as a precaution against premature slipping.[J] Use a tough collodion, and otherwise proceed as usual for the wet process. After the negative is finally washed and dried it should be varnished with a thin solution of gum arabic, to which has been added a few drops of a solution of chrome alum. After complete drying the margin or edges of the plate are rubbed with a little tallow. To prevent overflow the plate is accurately levelled and flooded with a solution of 10 parts gelatine soaked in 60 parts of water and dissolved by heat, to which is added 20 parts of alcohol and 6 parts of glycerine, using 1 dram of the solution to each four square inches. A few drops of phenyl, carbolic or salicylic acid may be added to the solution as a preservative, and the whole before use well filtered, while hot, through linen. The hotter the solution during the pouring on the more evenly the coating will run upon the glass, and it may be assisted in its flow by careful tilting of the plate. The use of paper strips is dangerous, and, notwithstanding the gum, extremely liable to damage the negative. [J] Instead of wax the plate may be dusted over with powdered French chalk, all traces of which are removed before applying the collodion. After such treatment the film is scarcely likely to leave the plate before required. But as a further precaution, if the edges of two plates be drawn across each other a rough edge will be produced, to which the collodion coating will adhere tenaciously.—TRANS.