The educational screen (c1922-c1956])

424 Among the Producers The Educational Screen LEARN TO WRITE PHOTOPLAYS From John Emerson and Anita IjOOs, two of the most famous, highest paid scenarists. Have written for Fairbanks, Mary Pickford, tlio Talmadges, Griffith, Ince, Paramount, etc. I^et Emerson Loos these masters teach you to write and soil scenarios. Big money in it. Profitable, legitimate side line for teachers. Oiiportunities for you in both regular photoplay writing and in tlio Educational and Industrial visual field. Write today. FREE BOOK— "Photoplay Writing" and Profit Sharing Plan. Laird Extension Institute. 512 Laird BIdg., IMinnoapolis, Minn. scopic movie camera which Dr. Herm has perfected at his Fifth Street studios. Dr. Herm -was formerly connected with the American Museum of Natural History but of late years has devoted his time to the development of the microscopical movies. Taking miscroscopic pictures automatically, every ten seconds, every two minutes, or at any interval desired, this machine can record the details of chemical reaction, the action of white corpuscles and the growth of new tissues in the healing of wounds, the building up of fine crystals from solutions, or the gradual changes inside the egg of a fish from the original clear fluid to the fully formed baby fish. Operated night and day for two and even three weeks, this camera has made records of scores of biological and chemical processes hitherto incompletely observed. One of the most interesting of the films so far made is a miscroscopical study of the life cycle of the oyster. The oyster lays eggs by the thousands and scatters them in an unfertilized condition in the water. The male oyster impregnates the waters with great quantities of sperm which are individually so minute as to be difficult of detection by the microscope. The chance meeting of the two. varieties of cells fertilizes the eggs and starts the young oyster on its career which is ended ninety-nine times out of a hundred by predatory minnows. Those which escape, however, are still numerous enough to keep the oyster industry flourishing. Cilia or whiplike processes soon appeared Bargain List of Slides A recent purchase enables us to offer slide users and distributors a large list at less than half price. Write for Bargain List. nil Center Street DeVRY CIRCULATIONS Chicago, 111. WANTED— Victor Safety Cinema, with 110-volt motor and rheostat complete, state condition, number, and lowest cash price. Box 7, The Educational Screen. with which the new hatched oyster rowed itself through the water with great speed. Just how the minute oyster larva propelled itself was not known before. It shot about with a speed which prevented the movement of the whips to be observed by the naked eye. Taking the pictures through the microscope at high speed and then showing them at low speed, however, made the rowing motion discernible. After acquiring the whips which enabled it to charge in all directions for food the oyster gradually acquired one shell, then another, and its after life was uneventful. Another film taken over a period of weeks by this patient camera was the biological history of an infusion of hay and water. Bacteria first developed in such quantities as to cloud the water. The water cleared, as the protozoa, the smallest animals, multiplied and ate up the excess bacteria. Then appeared the rotifers, a little more highly organized, which live on protozoa. But the rotifers fattened themselves on the protozoa only to become themselves the prey of various water worms. Hundreds of amazing feats of gluttony were exhibited with one drop of water for an arena. Dr. Herm works with the zeal of a scientist engrossed in his task, not seekinp' the plaudits of the multitude for his accomplishment. His scientific investigations revealed by the films are so amazing as to be almost unbelievable and their possibilities as an aid in medical research and educational fields are limitless. THE FHISTORICAL CHARTS OF THE LITERATURES ENGLISH AMERICAN FRENCH GERMAN Now ready'in revised and uniform editions. Send for the new circular— with miniature reproductions of each chart. THEfEDUCATIONAL-SCREEN 5 SOUTH WABASH AV., CHICAGO Please Write to Advertisers and Mention The Educational Screen