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740 THE PHOTOGRAPHIC NEWS. [November 23, 1888. first that have been regularly used for the illustration of a series of articles in a general newspaper. We allude to the series of “ St. Stephen’s Portraits,” which have been running tor more than three months in the St. Stephen’s Review. It is interesting, then, to note that as regards the present revival, one must accord both priority as to the patent, and the first commercial success, to Herr Meisen- bach. Our readers need only look at the magnificent portrait of Sarah Bernhardt, which forms our supplement this week, in order to be thoroughly convinced that Herr Meisenbach, if not actually first as regards the quality of his phototype work, has at any rate not been leit behind by those who have competed with him since the date of his patent. It must be remembered that the specimen we present to our readers has not been printed at the hand press, but on a quick machine. Various modifications of the “ network ” method of breaking up the half-tone have been carried out, and Mr. Ives sends us a small but admirable phototype portrait from a block obtained by this much patented method. Mr. Ives places a suitable grating between the lens and the sensitive plate, so that a grained negative is obtained. From this negative a Woodburytype relief is made ; and this relief, when reproduced by the electrotype process, forms the printing block. We have tried this form of the grating method, and find the result to be good. The grating used was a photo graphic positive of a piece of network ; this being im mediately in front of the sensitive plate. Although most possible variations of the grating process have been claimed over and over again by patentees, we do not know of any patent now in force which can hinder the free use of the grating method in this form. Our readers are aware that Messrs. Brown, Barnes, and Bell have recently given much attention to the production of phototype blocks from graduated negatives, and a speci men of their earlier work will be found on page 580 of our present volume. We are pleased to be able to state that they are progressing satisfactorily in their experiments, as the subjoined example of the irrecent work will show. We understand that one method which they practise at present is an ingenious application of oblique lighting on a ronghened or indented print. They indent an ordinary silver print by passing it along with a sheet of wire, gauze through a rolling press, and the indented picture is now illuminated by oblique rays, so as to throw the grain into relief; so that a negative taken in the ordinary manner is found to possess that grain, or stipple, which fits it for use in the production of a type block by the usual methods ordinarily used for line or dot subjects. The system in question appears to be very well adapted for the rapid pro duction of commercial blocks ; but as far as our own observa tions go, it is not capable of yielding those solid blacks which form an integral, although small, proportion of a perfect reproduction ; while the whites become somewhat extended. In other words, the fainter gradations of tone are lost. We have not yet made a thorough search with a view of finding how far this principle of producing a grained negative by the oblique lighting of a print is covered by previous or existing patents, but we could not find it in either one of the published patents of Messrs. Brown, Barnes, and Bell (present vol. pp. 265 and 602), although one of these contains, among a mass of other matters, a claim as to the use of indented prints in the production of blocks; but it is not stated how they are to be used—not a word about the feature of oblique lighting, or even the making of a grained negative from the indented print. Possibly they may assume that methods of making a block from an in dented print are sufficiently well known to experts ; but we presume that they have covered the method in some way by their new patent not yet published (see p. 649)' A very simple form of the network method, and one calculated to give high class results in the hands of a careful manipulator, is the following. An ordinary photo lithographic transfer is made from a usual negative, but between the negative and the sensitive paper there is interposed a film photograph of the required stipple or grain surface. The negative and film photograph should not be too dense, and the transfer should be developed somewhat slowly, so as to allow time for the moisture to disintegrate the granulations. One advantage of this method is the ease with which it can be taken advantage of by the ordinary photographer, who need do no more than send a negative and the stipple-film to a phototype etcher, such as Swain, in Farringdon Street. The stipple-film may be either a negative or a positive, according to circum stances, and, like the negative, it should not be too dense. We are not prepared to offer an opinion as to how far the photographer who merely sends his negative and stipple film to the zinc etcher may fairly claim to be the producer of the block. As the network method in one form or another appears likely to acquire increased commercial importance, we intend to devote a little time to tracing out its gradual development from the time when Talbot first patented it in 1852. COLOURED PHOTOGRAPHS ON GLASS. In the Moniteur de la Photographie, M. E. Perrot thus describes, in brief, the method he has found most successful for producing the convex coloured portraits now so popular. We have already described the modus operandi at length in these columns, but M. Perrot puts it so tersely, we may well give his words. Here they are : Warm gently the glass to which the picture is to be transferred, and coat the surface with Venetian turpentine. Use a very hard brush to give as thin a coating as possible. Wet the print, dry between blotting-paper, and apply it to the glass. To facilitate the drying, the glass may continue to be warmed. . The paper is next wetted, and gently removed by scraping with the fingers, and finally with pumice s one. The print is covered with spirits of turpentine to give i