Having thus fully described the nature of my improvement in photographic pictures, and shown how the same may be accomplished, what I claim therein as new and desire to secure by Letters Patent, is:-- The obtaining _positive_ impressions upon a japanned surface previously prepared upon an iron or other metallic or mineral sheet or plate, by means of collodion and a solution of a salt of silver and a camera, substantially as herein described. Hamilton L. Smith. Geo. T. Chapman. } _Witnesses._ James H. Lee. } _Dated February, 19th, 1856._ * * * * * PHOTOGRAPHIC PICTURES ON OIL. _To all whom it may concern:_ Be it known that I, Joel Haywood Tatum, of the City of Baltimore and State of Maryland, have discovered or invented a new and useful preparation of oil ground or body, and mode of preparing the same by which Photographic impressions, such as portraits of all sizes, landscapes or still life may be produced upon such oil prepared ground body or surface, whether upon canvass, mill-board, pannel, or other body whatever, without any permanent injury to such body, ground or surface for the reception of colors in oil (water) or dry (paste), without impairing the texture, quality, durability, or other desirable quality of the body ground, or surface rendered so impressible, and give the following as the Process used in accomplishing the result. I take ordinary prepared canvass, mill-board, pannel or other substance for the reception of oil painting by any composition of oil (or oleaginous substance) and oxide of lead or zinc, Spanish whiting, Fuller's earth, or their equivalents, singly or in combination, and after having removed all irregularities or lumps from the surface I damp or wet the surface with spirits of wine, and wipe clean; after which, I treat the surface with a solution of potassium or any good alkali, regulating the strength to the amount of oil in the body-ground or surface to be treated (ordinarily 1 oz. of super, carb. soda to 1 pint of water), as soon as the surface has uniformly changed color allow the surplus solution to run off, wash off by pouring over the surface clean water, let dry, but not by the fire or in the sun, as that would bring out the oil to the surface. When dry, treat the surface again with a solution of the chloride of sodium (of the strength ordinarily used and prescribed for paper positives), decant from the surface the superfluous fluid after a minute, and let dry, as before; remove to a dark room, and treat the surface with a solution of the nitrate of silver, its strength being governed by the strength of impression desired, usually 18 grains of nitrate of silver to 1 oz. of distilled water; allow the solution to float upon the surface a few moments to insure uniformity of deposit, and then decant the surplus, in the bottle or lath; place a small piece of filtering paper on the