Photography and Science.

New Zealand Graphic, Volume XL, Issue 8, 22 February 1908, Page 43

Photography and Science.

ARTIFICIAL CAMPHOR. Artificial camphor, the production cf which has heen a problem among chemists for many years, seems to be at last a commercial product, but the high price »f turpentine oil may prevent it from coming quickly into use. At least four processes have been devised for making this product from pinene, which forms seventy per cent of turpentine oil. By chemical treatment and oxidation, the pinene is given the chemical structure and chemical properties of the natural Camphor, but with different re-action in polarised light, and somewhat less fragrance. About ninety per cent of the world’s camphor is used for making celluloid, for which the synthetic, or artificial material is claimed to be perfectly suitable. ♦ ♦ ♦ SIC TRANSIT GLORIA. There came a member to our club—l dare not tell his name— A really fine pictorialist, of more than local fame. We showed him of our modest works, the evening that he came. We showed him of our portraits, and our landscape work in gum. He looked the pictures up and down, and then he murmured, “Hum!” Expressed the same opinion on our works in platinum. We showed him gorgeous carbons, and a kallitype or so. And some awful prints in oil that we were keeping for our show. We said we'd done some ozotype. To that he answered, “Oh!” He didn’t seem at all impressed. And then at last said we, “What medium is it gives you, pray, those fine results we see?” » « * « “What, mine?” he said. “I always use self-toning P.O.P!” —From “Photography.” ♦ ♦ ♦ HYPNOTISM RESTORES HAIR COLOUR. Dr. 11. E. Wingfield reports the case of a woman who came to be treated for mental depression, says “Science Siftlings.” Her attacks of depression were brought on by mental shock. She had not laughed for six months. But the extraordinary feature of the case is that in all her attacks her hair, which on her head is naturally a dark auburn and on her arms quite, fair, had turned quite black. When she recovered from her previous attacks her hair had recovered its natural colour. Dr Wingfield “hypnotised her lightly on a Monday for the first time, and told her to come again on the Wednesday, and on that day she was much better as regards her depression, but what struck me most was that her hair was fairer. To make a long story short, she was hypnotised in all six times in ten days, and at the end of that time not only was her depression gone entirely, but her hair had returned to its normal colour. The hair on her arms was then so fair as to be invisible at a short distance.” ♦ ♦ MOUNTING PHOTOGRAPHS. Lecturing recently, Mr. J. C. S. Mummery, president of the Royal Photographic Society, gave some useful hints on mounting photographs. A few of them follow:— White mounts are seldom suitable for photographs; tinted ones are usually better. The mount must set off the picture, not ornament it. The print must always be of first importance; the mount never Commanding first attention, either by its Colour, shape, or arrangement. As a general rule, the best shape for a print is one in which the sides bear to onC another the proportion of 3:2. More space should be given at the bottom of a picture than at the top, and

it is well to have as much variety in size of margin as possible. The width of the mount should never be equal to the width of the print, nor should it be equal to half the width of the print. Two-thirds the latter, or considerably more, is preferable for the width of the mount. The colour, of the print and the mount must not blend in an indefinite manner; the mount must be decisive, but quiet. Prints are best hung on the mount wi 4 th little dabs of seccotine, which are spread along the top, any excess of the same being removed. It is almost impossible to avoid cockling when several pieces of thin mounting paper are pasted together all over. It is most important that the print should be cut square. The simplest and best way is to use a tee-square and drawing board, pencilling the outline of the print, which is then cut on a piece of zinc, the ruler being preferably a steel ■straight edge. Zinc is better than glass, as it does not blunt the knife edge. In the case of cut-out mounts, the print is glued on, and then placed under considerable pressure until quite dry, when it should not show any cockling. For exhibition work three or four prints should be mounted in different ways, and it is then quite easy to select the best one. The same attention should be given to the frame as would be done in the case of a mount, making it harmonise in colour, tone, and weight. The mount and the frame should not be equal in width. The custom of framing close up is not so prevalent as it used to be, mounted prints, small in size, in narrow frames, being considered more pleasing and artistic. The passe partout method of framing was one which Mr. Mummery himself strongly recommended. In this method the print and mount are placed between a piece of glass and stout cardboard, and the whole bound like a lantern slide, with a suitable tint of paper. A waterproof “pitch” paper is recommended for the backing of the passe partout. This method has the advantage of harmony of effect and economy. Its chief fault lies in the direction of durability. ♦ ♦ + TWO EGGS A DAY FROM A HEN. In a recent issue of “Science,” Professor Gilman A. Drew, who has been conducting experiments in connection with the egg-laying possibilities of hens at the Maine Experiment Station, quotes instances of hens which have laid two eggs within twenty-four hours. The most interesting case is that of a pullet, which laid two eggs in one day early in March, 1900. During March and April there are records of five days on each of which this hen laid two eggs. Although she was carefully’ watched for more than a year and a half there are no records of her having laid more than one egg in a day. It should be added that the records of days on which she was known to lay two eggs came during the months of her greatest egg-producing activity. Professor Drew has noted a number of instances of hens laying two eggs in a day, but the records show that in most cases on either the day before or the day after that on which two eggs were deposited no egg was laid. Such cases may reasonably be accounted for by supposing premature or delayed delivery, but this cannot be true of the hen whose record has been given, where, for the five days beginning with April 3 and ending with April 7, eight eggs were laid. There are two other instances where an average of more than one egg in a day for a limited period was made. In both of these cases the possible mistake in the reading of the numbers on the distinguishing bands by which the hens are identified is to be considered. There arc eight other instances recorded where hens laid two eggs in a day, but in all of these cases on either the day previous or succeeding the day on which two eggs were laid no egg was laid. More interesting than these abnormal occurrences is the report of hens which at the station have laid 255 eggs within twelve months.