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Show I Why We Become SHORT-SIGHTED ! I! TUT HY cl EO 31finy -.of 1,5 uecorac snort j X sighted when nature obviously in-tended in-tended us to have normal sight? 1 The reason lies principally in the ralsnse of 1 the eyes during a brief period of childhood. Dr. Bogdan, of Budapest, has just published I an account of his examination of 200 school I text-bookB from a sanitary point of view. He J has hero dravn particular attention to the fact, already established by many prominent investigators, that, short-sightedness in chll- dren either originated or developed in connecr I tion with school education. The chief causa- I tive agency was. in fact, to bo found In too I prolonged reading, writing and drawing, fl whereby visual accommodation as well as I convergence were greatly fatigued. Undue R strain of the muscles of accommodation m caused an active hyporaemia; the return flow of the vonous circulation was greatly hln- 1 dered, there was an increase of the intra- I ocular pressure, and the outer coat of the 9 eye was gradually stretched. Too strong convergencp worked even greater harm for 09 the eye in various ways, Gloasy Paper (A) Reflects Uto Hsht Back Into Reader's Eyes. Rough Paper (B) Absorbs Light and Is Uninjurioui. ' ' ' i "'. ' v . ",. . j V. It must also he observed that in some of the children short-sightedness was hereditary. and they became affected much sooner than ! their healthy comrades. In addition to the 1 above causes producing short-sightedness. mention must be made of insufficient adinls-1 slon of light In many schools; a similar re-'! mark applied to unsuitable desks and other,1 school furniture. As regards tho influence of1! books on the eyesight, Dr. Bogdan Insisted that paper should not have a glossy surface, i for under artificial light a surface of this kind ( prevented the eye from seeing well and ne-) cessltated moving the book to and fro. :is well as frequent changes in the position of the ) head. Again, the paper should be thick ( enough lo prevent the printing of the next ) page from obtruding Itself upon the reader's f eye. A few authorities have recommended i yellow paper, but the majority were in favor ) of white paper, which gave a better contrast ( between the printed matter and the back- ground. In any event, however, the paper should bo rough or dull-surfaced enough to J absorb the light V |