London South Collegiate Institute - Oracle Yearbook (London, Ontario Canada)

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40 the law of inverse squares. can be reflected but cannot be refracted. The uses to which X-Rays have been put are many. By far the most out- standing use has been its application to pure science as a means for measur- ing the constitution of matter. From this came the discovery of radium by Madame Curie, the modern concep- tion of the atom with its far-reaching effects in the applied sciences Cradio for instancel, and the tremendous stimulus to astronomical investigation of the physical nature of the universe. In medicine it has been a great aid to the physician in the diagnosis of many obscure diseases and in the treatment of many serious as well as trivial conditions. More recently the X-Ray has been used in the detection of spurious works of art and more recently still it has been used for the detection of flaws in metal castings. Such use in commerce is bound to develop tremendously in the future when one thinks of the many metal parts that break in auto- mobiles and airplanes, due to faults in the manufacture, with disastrous results to life and limb. Rayon from Cotton Most of the rayon manufactured at the present time comes from wood pulp. The cellulose is extracted by a chemical treatment, which dissolves out the fats, resins, and other materials. It is then treated with other chemical agents, chiefly sodium hydroxide, and finally the resulting sticky substance is forced through tiny holes as in a sprinkler. When dried, the fine threads which emerge from these holes closely resemble silk. These are then woven into rayon fabrics. Spruce is the wood chiefly used in producing rayon. However, with the increasing demand and the prospects of an entirely new textile resembling wool from this source, it may soon be necessary to find a substitute for spruce. At the present time, cotton is'pro- duced only with considerable care and expense. It is planted in rows about four feet apart, and subjected to much cultivating. In harvest time the cotton is picked by hand and ginned while the stalks are left in the field. In this new method of produc- L. S. C. I. ORACLE ing rayon the whole plants-both stalks and lint-is utilized. The crop can now be mowed like hay, ginned and baled without picking. This greatly reduces the expense of producing cotton. Then, too, as the plants will be crowded to- gether, they will mature faster than in the old way, and so will produce more lint, relative to the size of the plant. Thus the cellulose yield of the whole plant may be raised to about sixty-live per cent. The new method of sowing cotton will practically elim- inate cultivation, and is expected to produce better and cheaper rayon. V -G. M. L. EDISON AND ELECTRICITY Although there are over twelve hun- dred patents registered in Edison's name, most of his active life was de- voted to inventions of an electrical nature. The most important of these are the incandescent lamp, and the system for the transmission of electric current for producing light, heat and power. Edison himself considered his in- ventions leading to the development of the electric light and power industry to be most important, for, until his time, electric lights were known only in the form of powerful arc lamps to illuminate streets. After more than a year of concentrated effort he succeeded by carbonizing a piece of ordinary thread, in making the first incandescent lamp, which, when placed in a circuit maintained its incandescence for over forty hours. In two months these lamps were perfected to such an extent that a public demonstration was given. Two years later a factory was estab- lished and almost immediately elec- tricity became the most popular means of illumination. Edison went on to improve the dynamos, and the means of determining and distributing the current produced by them. He also perfected sockets, switches and various other appliances to facilitate the use of electricity in the home. E The inscription on the United States Congressional Gold Medal In com- memoration of his achievements in illuminating the path of progress through the development and application of his inventions, expresses the sentiment of a grateful world.-JEAN PHILLIPS.

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L. s. c. 1. ORACLE 39 4 1 ' k ill? i X E-E f 5 Q - me : E fin ,- N I - if 2 1 if M Editor, GEORGE LAMONT, IV B THE X-RAY By H. S. WISMER, M.D. Radiologist. To submit a short article on the X-Ray one must be content to simply jump from one high peak to another. When Conrad Roentgen first dis- covered this new type of energy he opened up such new wonders in the world of physics that we are only now beginning to realize its far-reaching effects and future potentialities. It is only necessary to recapitulate the apparently disjointed connections be- tween Faraday's electrical researches of a century ago, Daguerre's discovery of photograph, Crookes' low-pressure gas tube, Stokes' work on Huorescence and Roentgen's astute observations on the behaviour of fluorescent screens and photographic plates in the vicinity of a Crookes' tube to grasp ,something of the romance of X-Ray. . Roentgen's discovery came in 1895 and was immediately given to the world. Science at once grasped its significance and medicine was, perhaps, the first of the applied sciences to put it to prac- tical use. Here was an agent to pene- trate solid material. Indeed there was now no such thing as solid material. Matter was now built of infinitely small bricks with great wide inter- stices capable of allowing a ray to easily pass between its bricks For the iirst few years progress was slow but soon acquired momentum, particularly during the World War. . For a comprehension 'of the physics of the X-Ray tube it is necessary to have a working knowledge of the nature of matter as twentieth century physics sees it. Dalton's atomic theory taught the 19th century savants that the atom was the smallest particle to which matter could be subdivided. 20th century physics takes the little hard 19th century pellet and reconstructs as a small solar system with a central sun or proton revolving around which are from one to ninety-two planets or negative electrons. This model of the atom is not exactly correct but serves as a good working theory. An X-Ray tube is composed of a glass bulb exhausted of atmospheric air as far as possible with two terminals, an anode and cathode. f The first tubes used were gas tubes which depended on gas introduced into the tube and the later types are not cathode tubes. The principle in each is the same. When the tube is energized by a high poten- tial current the negative electrons are torn away from the atoms of either the gas in the gas tube or the heated filament in the hot cathode tube at the cathode terminal. These How across the intervening gap between the two terminals and are bombarded against the anode which is specially constructed so as to present a target which is inclined at an angle to the stream of electrons. This electronic stream is known as the cathode ray. It travels at thousands of miles per sec- ond and produces at the point of impact a ray which travels outward in all directions. This is the X-Ray. Its wave lengths are very much shorter than light. It has the same velocity as light, 186,000 miles a second, obeys

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L. S. C. I. ORACLE 41 n - ..i I .- A - N TURAL. .r....L, L A p Editor, BOB MCLEOD, V B FEEDING THE WINTER BIRD Such a vast amount of knowledge is included under the name Natural Science that it would be impossible for any one person thoroughly to peruse the entire subject. But Natural Sci- ence has so many various phases, all of which are intensely fascinating, that there is a subject to suit the taste of every person who does not stop up his ears to the voice of nature or blind himself to her beauties. To my mind the most interesting of these departments is Ornithology, and at this particular season it is appropriate to consider the feeding of winter birds. l an-Ja'-'H'-'-'rv ---l--:i:.T:- - - ' --x 1 ' -.J --., , .5 . , , - - ,........- v,,,., - 5:Z .:.-::7,f- ' j ' ,-1-in ---- ' ,lg--42, li! This is one of the most interesting of winter pastimes, and one which involves very little expense and only a few minutes of work each day. Before the winter storms come many of the birds migrate to the south. On the other hand there are over twenty common species that regularly stay with us during the winter. In London dis- trict alone, thirty-live species were ob- served in a single day. This was the result of the observations of the people taking part in the annual Christmas Bird Census of the Macllwraith Orni- thological Society. During the three winter months, December, January and February, there have been observed in Middlesex County nearly eighty species of birds. t However, although a person cannot expect to have many species of birds attracted to his feeding station, he may be reasonably sure of having at least two or three if he will provide food and water regularly. A great deal of the birds' natural food becomes covered with snow so that many birds perish during the winter from lack of food. For this reason several species forget their fear of man and come to the source of supply. To insure their visits regularly the bird feeder must renew the food. If the birds come and find that there is no more food they are very apt to forsake that particular feeding station and seek food elsewhere. The best and cheapest foods are sunflower seeds and suet. These will attract nearly all the winter birds, although it is wise to supply also millet, for the benefit of such birds as the junco. Enough sunflower seed to last several seasons can be bought for twenty- five cents. An interesting field for inves- tigation would be to experiment with different varieties of foods to find out which are most acceptable. There are several methods of offering suet. A lump of suet may be covered with wire netting and nailed to a tree. this prevents any large birds such as a bluejay from carrying off the Whole piece. On the other hand it is dangerous as the bird's tongue or eye might be injured by sticking to the frosty metal. A safer method is the use of the feeding stick. This can be easily made by boring holes about one inch in diameter and half an inch deep in a small log four or live inches thick and about fifteen inches long. A log with rough bark such as elm is