Jump to content

Popular Science Monthly/Volume 51/September 1897/Minor Paragraphs

From Wikisource

MINOR PARAGRAPHS.

It is reported that an important advance in color photography has been made by M. Villedieu Chassagne and Dr. Adrien Michel Dausac. The process is simple and inexpensive. A negative is taken on a gelatin plate, which has been treated with a solution of certain salts (the nature of the solution is kept secret). The negative is developed and fixed in the ordinary way. From it a positive is printed on a sensitized paper which has previously been treated with the unknown solution. This positive is then washed over with three colored solutions—blue, green, and red—and it takes up in succession the colors in their appropriate parts, and the combinations of the colors giving all varieties of tints.

Berthelot and Vieille have recently been experimenting with acetylene, in reference to its explosiveness. They found that when acetylene at ordinary pressure is exposed to the action of the electric spark, a red-hot wire, or a fulminate shock, the gas is decomposed only in the immediate vicinity; when the gas is under pressure, however, the result is quite different, the acetylene acting as do the ordinary explosive mixtures when the pressure exceeds two atmospheres—the explosion rapidly spreading through the entire mass which, decomposes into hydrogen and finely divided bulky carbon. Liquid acetylene behaves in the same way. Using eighteen grammes in a bomb of 48·96 c. c. capacity, the final pressure was 5,564 kilogrammes per square centimetres—almost the equal of gun cotton.

Stress is laid by M. Albert Gaudry, in his study of Philosophical Paleontology, on the increase of intelligence as a feature of animal development. First, there was progress in locomotion, and the sedentary invertebrates of Primary times were succeeded by the secondary reptiles, and they by the numerous Tertiary mammals. The continued improvement of the last was manifested in the gradual adaptation of the feet of the horse and deer, making them better fitted for speed. The power of sensation has also undergone a steady augmentation, and intelligence has been developed slowly and regularly. If, in the absence of other knowledge, we may judge concerning the nervous system of the invertebrates or of the Primary fishes from that of existing beings, we have to conclude that their intelligence was very imperfect. The forms of the brains of some of the Secondary reptiles, as revealed by molds of the interior of their skulls, show that they were very little advanced. By this criterion, the gigantic saurians were very stupid animals. A progressive development evidently took place during the Tertiary period. Finally, the brain of man, the latest, is the most complicated, the most voluminous, and at the same time the most condensed of all. The history of the world thus reveals to us a progress which has continued through the ages.

The utilization of burned clays as a road material is mentioned in Mr. C. B. Keyes's last Missouri Geological Report as a subject that should be fully discussed. Some of the railroads are already using burned clay for ballast in preference to rock, sand, or gravel, with good results, so that the extension of the use of this material to highways is in reality beyond the experimental stage. Prof. Wheeler says in his report on clays that, while it is not so good as tough rock for the heavy traffic in cities, it would prove durable for country roads, where the teams are few and the loads light. It can be prepared wherever the clay is, and often by the roadside; and as the heaviest roads are those in clay soils, these may be made themselves to furnish the material for their own improvement.

The failure of British girls' schools to achieve the results intended in scientific training was ascribed by Miss L. Edna Walter in the British Association to the two reasons that only the faculty of observation is, as a rule, cultivated, and that the work is not begun low enough down in the school. A gently graduated scientific course is, in the view of the author, wanted, beginning with the simplest experiments for young children, and gradually increasing in complexity till the girls reach the age of about sixteen. From beginning to end the course should be practical in character, and quantitative as far as possible. Such a course can be followed if practical arithmetic be made the starting point. This leads naturally to elementary physics, chiefly hydrostatics, and finally to a course of elementary chemistry. It is an important feature of the course suggested that the children should use no textbooks; their own notes written in their own language should form their books of reference. In this way their literary powers are cultivated; but, above all, they learn to rely upon themselves.

A remarkable discovery has been made near Perm of an extensive burial place of the supposed old inhabitants of Russia, the Chuds, from which exceedingly rich collections of implements have been recovered. Among them are at least a hundred earthen-ware vessels, and "cart loads" of broken pieces of earthenware ornamented with all sorts of figures illustrating the life of the people. Of these are men sitting on horseback and in small boats, nine engravings of bees and flies, fifty-nine engravings of birds, more than a hundred of different mammals, and ten of snakes. Three masks and one head of mammals were also found, a large silver plate representing a man standing on some animal, eight smaller silver pieces, a hundred and forty one bronze plates, several bronze statuettes, and "an immense number" of rings, stars, bells, small models of sledges, thimbles, arrowheads, hatchets, knives, nearly four hundred gilded bronze pearls, fishing hooks, skulls of stags, various carnivorous animals, etc.

It is stated by Prof. T. F. Wright that recent exploration in Palestine clearly shows that all the ancient chronicles in regard to the wall of Jerusalem were trustworthy. It had a very strong wall, with frequent towers or bastions. The wall ran all around the brow of Zion Hill, crossing the Tyropæan Valley, and then going northeasterly to the corner of the temple inclosure. As it will be represented on new maps, the present wall on the south side will be a nearly straight line, placed east and west, with a loop southward from its ends like a bow with cord loosened. The space between the straight and the curved lines has been very little explored as yet, but at the pool of Siloam Dr. Bliss has found the perfect formation of a very early Christian church, showing its whole plan. This place will be kept open, and will be one of the most interesting places in or near the city.