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It would be a pity to let such a happy idea rest; with a little ingenuity it might be developed, nay improved upon, in a hundred ways calculated to afford harmless pleasure. All sorts of societies and associations might be formed, the members publishing the rank they consider themselves equal to. Take the Photographic Society, for instance: why should it not be announced that in future baronets will be elected without ballot or scrutiny ; or there is no reason, indeed,why present members should not declare themselves equal to a duke or ambassador. In fact, the only fault we find with the circular of the Institute of Chemistry is, that it doesn’t go far enough. Professor Pickering’s paper on his method for determining the light and colour of the stars by photography, read at the last meeting of the Royal Astronomical Society, was a very important one—a combination of lenses giving a large angular aperture, and a field in which there was not much sensible aberration at a reasonable distance from the centre of the field. With this combination stars down to the fifth and sixth magnitude left a trace on the plate. An exposure of ten seconds was made, during which time the earth’s motion is so small that the images of the stars only appear as circular dots. The camera is then covered up for ten seconds, and another exposure of thirty seconds is made, so that the image of each star is made by a dot and a dash. As might be expected, the colours of the stars have much to do with the resulting photographic image. Thus those that shine with a red light are much more indistinct than those which are blue. To overcome this difficulty Professor Pickering intends to utilise the fact of the difference in the length of the focus for blue and red rays in a nou-achromatic ray. He proposes to cut out the centre of the lens by means of a prism of small angle, and this will obtain, he says, “a species of monochromatic photograph, for it is only the light which is brought to a point which will be intense enough to register itself upon the plate, and so we shall practically get photographs corresponding to different colours for different distances of the plate.” The Gas Institute, meeting last week at Sheffield, had the question of a standard light before them. The standard candle was denounced, as it has been denounced many times before, and Mr. Vernon Harcourt read a paper on “ The Pentane Standard and a]New Form of Photometer.” He argued that it would be beneficial if the French Govern ment could be induced to join us in investigating the ques tion of the standard of light, a subject of vital importance to photographers, we need hardly point out. The Pentane Standard, at present under trial in this country, means the burning of a certain mixture of air and petroleum vapour, twenty parte of air with seven parts of vapour. The light given off by a quarter-inch jet of this mixture—the flame being about two-and-a-half inches high —is about equal to that of a standard candle, but has the advantage of affording a more constant illumination, care being taken that the petroleum employed is that which distils at a certain temperature. In the Report of the Paris Observatory for the past year, considerable stress is laid upon the value of observing stations at considerable altitudes. It is proposed to build an astronomical observatory on the Pic du Midi in the Pyrenees, at the elevation of between eight and nine thousand feet. Here the atmosphere is so pure and clear that it is easy to read at night by the light of the stars alone, and of the tiny group of stars known as the Pleiades, it is possible to make out fifteen or sixteen with the naked eye. We in this country still go plodding on, taking photographs of the sun at murky Greenwich, the solar orb veiled in the mist and smoky vapour that comes over from the Isle of Dogs opposite. It is true that a proposition has been on foot for some time past to erect an observatory on Ben Nevis, but so far the scheme has met with scant encouragement from the powers that be. Fortunately, we may now hope for better things. This opinion on the part of French observers, as also the circum stance that Her Majesty has given £50, and the Prince of Wales half that sum, towards the Ben Nevis plan, will certainly induce a step forwards. A pathway to the top of our highest mountain is to be forthwith commenced, and let us hope that before another twelvemonth passes, funds will be forthcoming for the erection of a substantial observatory. Mr. Francis Galton has embodied in a volume entitled “Inquiries into Human Faculty and its Development,” the result of his experiments in “ Composite Portraiture,” a paper on which subject he read before the Photographic Society some time ago. Mr. Galton also repeats in this volume his plea for family registers, the weak point of which is, as the Pall Mall Gazette points out, that although families might be willing to record all the good pointe in their own favour, it is to be anticipated that they would cook the books on the bad side of the account. But a photographic family register pure and simple would be scarcely open to this objection. The preservation of indi viduality throughout a succession of generations is some times very curious, and especially when, as it sometimes does, appears to miss one generation and re-appear in the next. The singular resemblance between the very old and very young of the same family has often been noted ; but what is more singular still, is the unexpected resemblance which photography oftentimes reveals. Skits on photographic subjects are not uncommon in the German comic papers. In the Fliegende Blatter, the other day, a young lady was represented telling' her aunt that Herr Mller, an artist, had asked her for her photograph to paint from. “ If you send yours,” replied the aunt, “ then mine must go as well. It is scarcely proper that a young lady’s photograph should go to a painter’s studio without a chaperon! ’’ The fun in this is peculiarly Teutonic. More humorous, to our notions, is the story, also in the Fliegende Blatter, of the lady who took her child to be photographed, and on being told by the photographer that the light was too weak, begged him to try, as she was sure it must be strong enough for such a little fellow 1