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Show I OLD IDEA IN PHOTOGRAPHY. Uaa af Colors Was First Suggested In the Firms In the early Ma Polti-tln, a well-liiiiail well-liiiiail phoioaraphic vHrltni niallat, pu'niied a proiitm h whlih a photo-Ktaiihli photo-Ktaiihli Imnxe ioiiIiI he punud In a planient niln-il with ,11 li wmi In have been entlrel) nen-lei nen-lei ted by the photoKraphers of lhat time, and has lone, been forgotten Hut II haa quIU- nr.-ntly lieen rcdla-covered, rcdla-covered, and the method haa been seised upon li) advanred amaleurs as one peculiarly ntted to give them that control over the lljtht and ihadu of the prim which they ronslde- In-illapnnaable In-illapnnaable The proress Is briefly this IhhmI stiff rartrldfe papvr la coated wllh aelatlne, dried and subsequently sensitised sen-sitised in a 7 per rent bath of po laaala hlchromale Once more dried. It la i-tposed to llfjht beneath a nega live In the ordinary manner Hoaked In water, those portions of tho picture which have received moat lliht hate become Insoluble and do not retain moisture while the IlKhta" awell up and absorb much water It la proverbial that oil and water will not mix, and when a roller harited with oil tolor la applied lo ihe print only the Insoluble shadows will hate anything to do wllh tho lohir, they n-rtlve It. while tho lights uf ihe pit Hire repel It The pnxeaa la an Interesting one. and althuiiih of such ancient dale may lie regarded aa at III In an eaperl mental stave - Chambers' Journal |