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surface, which is effected under one method by hand— artistic manipulation, by stippling, lining, hatching, roughening or breaking up the surface or any portion of the surface; for example, by stippling with pigments or inks, or by abrading the surface, &c., &e.” Some months ago a circular'was issued by the above- mentioned firm, cautioning the public against infringing their patents. We hope they will be lenient with respect to those who have unwittingly infringed, as the above claim appears to cover every kind of retouching on a photograph or picture intended for phototypic repro duction. An announcement of interest to our lady readers, culled from the latest blossoming of the Photographcn Zeitung. “A young lady practised in all branches of photographic work, and in a position to undertake the direction of a studio, is hereby given the opportunity to take part in founding, extending, and furnishing the capital for a photographic establishment in a large town in North Ger many. In the event of their being mutually disposed, marriage, at a future time, with the advertiser is not im possible. Ladies favourably inclined are requested to send full address, portrait, and particulars as to capital, &c., confidentially to the office of the Zeitung, to G. R., 503.” We must ask our Publishers, however, not to copy this announcement into the “ Photographic News Registry,” for we cannot be responsible for breach or blighted hopes in the event of bad faith, though the fact of the advertiser being a careful, prudent man is very obvious from the method of his announcement. Those who now make use of “optical sensitizers” claim far more for them than ever did their originator, Dr. Vogel. The most successful of recent workers seems to be M. C. V. Zenger, who has just brought his results before the Aca demy of Sciences. He has been busy with solar photo graphy, employing for the purpose bromide plates stained with chlorophyll. Dried peppermint leaves were treated with sulphuric ether, and the resulting dark green fluid, on evaporation of the ether, became a black friable aromatic body; from this, by means of benzine, pure alcohol, and paraffin, three colouring matters were obtained, viz., green chlorophyll, indigo chlorophyll, and the reddish yellow xanthophyll. Each of these has its peculiar spectrum of absorption, and a bromide film impregnated with all three absorbs very nearly the whole of the solar spectrum. M. Zenger claims to have secured pictures of the corona and chromosphere, occasionally with the red and yellowish tint of the original. “I even obtained,” he says, "a photograph of a solar halo, very vividly coloured, on the 10th January, 1875, having all the tints visible to the naked eye, and to this day the colours on the plate have not changed.” M. Zenger assures the Academic that it is possible to obtain everything around the solar disc upon collodio-bromide emulsion plates treated with an ethereal solution of chlorophyll such as he describes. If Earl Cairns is really trying to buy up all the photo graphs of the beautiful Miss Fortescue—one of the three dainty fairies in lolanthe, whom his lordship’s son and heir is about to marry—we do not envy him his Herculean task. To get the photographers to whom Miss Fortescue sat to surrender their negatives is a comparatively easy matter, but to prevent the circulation of piracies is quite another thing. The more portraits Lord Cairns buys, the greater will be the supply ; and if only the demand is keen enough, the photographs will be on every hawker’s barrow in the street, retailed at a penny a-piece. By far the best plan is to let things be. The lady having once given permission for her portrait to be pub lished, for the purpose of advertising and making herself generally known as an artiste, it is very foolish to seek to withdraw it from circulation. Any attempt to do this is sure to frustrate the very end her friends have in view. As many thousands have paid a shilling to see the lady perform, surely the payment of the same sum for her photograph cannot be so very derogatory. " You say that your photographs are permanent; yet when I put them in water, the surface comes away at a touch!” ejaculated an indignant young lady who occupies her leisure with crystoleum painting. The photographer, who prides himself on sending out nothing but carbon work, tried to explain, but he failed. Dr. Tromholt, who has erected an observatory in the extreme north of Norway, for the purpose of observing the aurora borealis, where this phenomenon is seen at its best, says that “ to photograph the aurora borealis is an impossibility.” “ Not even,” he assures us, “by using the most sensitive English dry plates, and exposing them from five to seven minutes, have 1 obtained a trace of a nega tive. The cause of this is, I believe, the exceedingly limited substance of light possessed by the aurora ; were thus the entire heavens flooded by the most intense aurora, their aggregate lighting power would not equal that of the moon when full.” We cannot accept Dr. Tromholt’s verdict—at any rate, on the evidence adduced. As our readers know very well, not only is it common enough now-a-days to produce pic tures of the moon, but also of landscapes illumined by moonlight. Of course, these are not to be secured in “ from five to seven minutes,” and we cannot help think ing that by mounting a camera on an equatorial, and ex posing some hours, Dr. Tromholt would be successful in getting some kind of result from the aurora. Whether the aurora in a high north latitude remains constant suf ficiently long to impress an image of its shape upon a bromide film, we know not; but if it shines vividly for four or five hours together, we have no doubt that its light, and even its spectrum, could be recorded in the camera. The spring is the time generally chosen for re-painting the outside of houses, partly because the weather enables