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of them in dark lines. When dry and empty, they arc opaque, and, by preventing the action of light, produce white lines. Dried leaves may be made to give prints in all respects equal to, and sometimes- even superior to, those obtained from freshly- gathered ones, by soaking them for several hours in water until the veins become expanded and filled. They must then be pressed between the folds of bibulous paper until dry enough superficially to print from. After this treatment they will only remain in good photographic condition several days, but the operation can be repeated as often as desired. A little glycerine added to the water will cause the veins to remain transparent longer, and a little hydrochloric acid will facilitate the filling of the veins in some cases. When it is desired to print from several leaves upon the same piece of paper at the same time, it will bo found convenient to fasten them to the glass by means of dilute gum-water. Imme diately after being fastened to the glass in this way they should bo subjected to the pressure of the clothes-clip as in printing from them. In some, cases it is best to place the leaves—especially dried ones—between folds of writing-paper, and subject them to as great a degree of pressure as can be obtained by moans of an ordi nary letter-press, before fastening them on the glass. If the leaves are not of the same intensity, the most intense—those that require the longest time to print—may bo bleached as much as necessary by means of Labarraque’s solution, or those least intense may bo stained light yellow by moans of turmeric. Small plants with flowers that preserve their shape somewhat in pressing— as violets—can be photographed entire. As all prints taken from the leaves themselves must consist of a light image on a dark background, Professor Himes suggests that for many purposes an improved effect will be produced by using the print first obtained as a negative ; first treating it with wax, to render it transparent. The following is the method recommended:—Melt some pure white wax by placing it in a shallow dish placed in a pan of boiling water. Immerse in the melted wax sheets of blotting- paper. As these sheets will absorb much more wax than is required, a pile is to be made of (say) half-a.dozen of these with half-a-dozen clean sheets of blotting-paper, placing alternately waxed paper and clean blotting-paper, a few- extra sheets of the latter being placed at top and bottom. The whole pile is then pressed with a flat-iron heated to about the temperature of boiling water. By this treat ment a series of uniformly waxed sheets of blotting-paper will be obtained. When a print is to be waxed for use as a negative it is placed upon a sheet of blotting-paper, and then upon its face is laid a sheet of the waxed paper; this is then covered with two or three sheets of blotting-paper, and the whole pressed with the hot iron. The negative is thus uniformly waxed, and made sufliciently transparent for print ing purposes. Lucid instructions are given to enable the amateur who is not familiar with photographic operations to print from the negatives so obtained, either by the ordinary silver processes, by the ferridcyanide of potassium process or the bichro mate of potash process. With each of these processes most practical photographer's are familiar. We may, however, brieflymention here the formula for the two latter. The first of these gives blue prints. Prepare,— Ferridcyanide of potassium (red prussiate of potash) 100 grains. Water 1 ounce. Apply the solution with a tuft of cotton to a piece of Saxe paper pinned to a board. This will give paper of a uniform yellow tint. This, on exposure to light, becomes blue ; the only fixing process necessary being copious washing in water until all trace of yellowness is removed. A saturated solution of bichromate of potash produces brown images by similar treatment; excess of washing having a tendency to decompose the image of brown oxide of chromium, and leave a pale green image of sesquioxido of chromium. This volume opens out to amateurs in various studies a new means of preserving examples and patterns, and to botanists especially, suggests a method of study elegant in itself and invaluable as an aid to systematic progress. o titical Butins. THE PHILADELPHIA PHOTOGRAPHER. Vol. IV. 1807. (Philadelphia: BEXERMLAX and Wilson.) TIERE is no contemporary photographic journal which we take up with so much pleasure as the Philadelphia Photogra pher; none in which we are so certain to find something which will well repay reading ; it is, in fact, altogether a model of what a monthly photographic journal should be. The energetic and able editor, Mr. E. L. Wilson, is already assisted by many of the ablest writers on various depart ments of photography, and we note that he has just strengthened his staff by the accession of Professor Towler, formerly editor of Humphrey's Journal, who will now con tribute regularly to the Philadelphia Photographer. Amongst the writers whose valuable articles have aided in giving interest to the volume just closed, we find, besides that of the Editor, the names of Carey Lea (whose researches gene rally first appear there) Dr. Vogel (who is German corre spondent), the Rev. J. II. Morton, the Rev. A. A. E. Taylor, Professor Henry Morton, Coleman Sellers, J. C. Browne, F. A. Wenderoth, C. W. Hull, G. Mathiot, Professor 0. N. Rood, J. Zentmayer, J. Q. A. Tresize, Dr. Liesegang, and many others, all of whom contribute excellent original articles. A very interesting feature of this journal is the publication each month of a photographic picture illus trating some point of interest. A number of very capital cabinet pictures appear, amongst other subjects, in the present volume, and have, we doubt not, helped to popu larize its picture and secure its success. The question has at times been asked by some of our correspondents as to whether we could not occasionally issue examples of pro cesses in our pages, and we have had to regret its impossi bility, as the cost of almost any form of mounted photo graph would exceed the wholesale price for which a copy of the PnorOGRAPIIIC News is sold. In America a different state of things prevails. Photographic literature is not there nearly so low-priced as in this country. Here the standard price for a manual of instructions in photography is one shilling ; there it is one dollar, or four times the amount. The price of each number of the Philadelphia Photographer is half-a-dollar ; but we consider it cheap at that sum, and commend it to any of our readers who, in addition to excel lent information, would like to see a good example of pho tography every month by a first-rate man. We may add here that our esteemed friend, the Editor, has made arrangements to send us advance proofsofany important original articles which appear in his pages, so that our readers will have the earliest access to any interesting mat ter in connection with photography transpiring amongst American photographers. ON THE PRODUCTION OF PHOTOGRAPHS IN PIGMENTS: Containing Historical Notes on Carbon Printing, and Practical Details of Swan's Patent Carbon Process. By G. Wharton Simpson, M.A. (London: Thomas Piper. Newcastle: Mawson and Swan.) For obvious reasons we cannot enter into any notice of this work beyond noting the fact of its issue, and briefly mentioning its contents. After a brief resume of the history of carbon printing from its origin until the present time, the chief part of the work is devoted to a minute statement of the practical details of all the operations in Swan’s carbon printing process. These instructions arc based on a careful observation of the operations in the Newcastle carbon printing establishment, and upon observations during much personal experiment and practice; and they are moreover made authoritative by having undergone Mr. Swan’s exami nation for verification or revision. There are, also, chapters on the theory of the action of