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Show r I Science's Curious New Discoveries About Our Eyes I Striking New Theories Which May Explain the Wide Variations I I in the Gospel Accounts r; v; J I of Saviour's I Crucifixion ami Clear I I .. Up Many Mysteries $7 ' ' I . ;.v.''x . l.. . - .. About the Vision of . J f I -::;sr .y- - Men, Animals, Bird? I Mr I I Showing Its Great Depth. Science Has Found That This Formation Is Mainly Responsible for "Depth Perception," and Not the Combined Com-bined Use of Our Two Eyes, as Formerly Supposed. MAXY scientists have been patiently studying the eye of men and ani mals finding out how wo see, whot H kind of things WS see most quickly, how our eyes aro deceived, and othtr interest- lng matters. B ' The result.- of thousands of lnvestiga- ) Hon? Into the eyes nre summarized by Professor Leonard Thompson Troinnd, of H I I Harvard University, in the Psychological B Bulletin. B The animals have eyes adapted to their B various ways of living. You hare probably k. noticed how the pupil of the cat's eye K. forms a narrow slit run n In it up and down I ijij; tho eyeball. The investigators have found H; that the pupil of pussy's eye has a Ion per H. vertical than horizontal nlr. because the M cat Is primarily a climhlnc anima', and this H t sort of pupil favors the perception of ob- H jects seen looking up a tree or down from j 1 a H The partly clored pupli of a sheep's eye Hj I is exactly iho opposite of the cat's eye, in U that It has a longer horizontal than vertical B axis This Is because the sheep needs to B take In the contours of the surrounding B lexMscape as far as possible. It is not a H climhpr. hut usually stands on flat places. B Being hunted rather than a hunter, it needs B the increased Illumination at the side? of H the eyes which is provided by the special B shape of its pupil H Studies have been made of the wonder- B ful seeing powors of the hawk and other B birds of prey. These animal? have point? B of most acute vision in the eye, called J "tpveae." Observations on the buzzard show that each eye functions separately B I and that tho "foveae" of each eye also act B independently, much as do tho fingers of H the hand In the "acute vision spot" H are tiny colored oil droplets. The colors 1 arc ye'low, orange and red. and their func- W tlODC arc probably to form a .protective The retina of the human eye has a j i fovea, or spot of most distinct vision, but Hj the fovea of the birds is finer and more B complicated than that of man B It Is interesting to learn that wasps and B some other Insects have good color vision B and are attracted by color and color con- B Iv trusts. Bright light stimulates the honey H! bee to active movement, and especially the K worker bee. When ono eye of a bee is Bj blackened the Insect moves la n loop in B the direction of the functioning eye. B Tho compound eye of tho butterfly and Hj other insects is sensitive to color and dls- Bj tance The butterfly distinguishes with H . its compound eye objects at a distance of H) an inch to three feet. H Just why the flies have compound eyes. H) consisting of hundreds of separate facets H ,'' has always been a puzzle, but the latest Hj if' experiments Indicate that they are used to H ' see very near objects. Hj Oysters and other mollubcs, which do H i ' not have distinct eyes' but nly vlcunl Ht'Vi cells, arc sensitive to sudden cbmces of H light. A mussol was seen tu respond to a H Ufcht after 1.3 seconds Hj i Many of the lower invertebrates have H j! j various types of vlsnal cells, which sug- H Jj gest the line of evolution vo the fully de- H p veloped vertebrate eye. Tho earth worm Hitj ' nas an ("c or visual cell, which l)..r-!v HjlJ,!: distlaamlithes light from darkness. The HIIvJ limpet has a visual cell which only per- H'liK celve? motion and direction. The eye of B!fvH the tube worm baa only a rudimentary H I i ! perception of form. v H.i ' i Mud mlnno3 and sticklebacks were B One of the Most Successful Examples Ex-amples of Camouflage in the War. A Ship Is Painted to Look Like Several. The Submarine Observer Whose Eyes Recorded Form Would Have Belter Chance to Penetrate the Disguise Than One Who Was Keener Upon Motion or Color. trained to associate food with certain colors. It was found that they could discriminate dis-criminate between red and both blue and green, and also between yellow and green although they are unable to different laU between blue and yellow All these experiments experi-ments on the lower animals help to ex plain the function of si?ht in man. which is a good deal of a puzzle. The most interesting facts observed with regard to man's eyes aro that each eye has a separate function, that different pnrts of the retina have different functions and that one per?on sees color, another sees form and another sees brightness with greater clearness than .another. Students of optics havo hitherto believed that a man perceives depth In a solid object ob-ject because he sees it with two eye?, and that it would appear perfectly flut if seen with one eye only. It has now been found that depth perception Is not mainly a func tion of the combined eyes, but depends on the fpet that the retinal Image of each eye has a certain thickness, positions within which are sensed. The fusion of separate Images Is not essential to stereoscopic vision, in which we see an object in relief, and a single eye ran obtain the stereoscopic vision. Previous Pre-vious experience Is the most important influenco In giving us this form of vision. The function of the retinal imago in each separate eve remain! Independent until the very highest levels of mental nssocla-tion nssocla-tion ;ire reached. The combined power of Judgment, experience and other factors I? more importunt in giving us an image, with all Its relations, than the ?imple binocular mechanism The Impression produced on the brain depends on whether the merhanlsm of the retina is stronger to perceive color, form or brightness, and finally in the power of fhe higher mental centres to put together the whole In I ge This explains why two frits esf6fl who see exactly the same scene retain very different improssions of it There hnvi? been innumerable cases in the law courts In which several witnesses who saw exactly ex-actly tho same scene differed radically In their statements concerning what th-v sav7. In many cases these witnesses were perfectly honest or without Interest in misrepresenting mis-representing what they saw. Judges and lawyers have for centuries been entirely unable to explain these extraordinary discrepancies. dis-crepancies. Now everything appears clear in the Huhi ... Irntlth Investigation On.- roan's retina is stronger In the part that records color; another in the part that record? brightness, another In tho part that perceives per-ceives form. Then, quite outside that, tho higher brain centres do not necessarily perceive the whole image that is thrown on the retina, but only those parts in which the per.-on is Interested. The same peculiarities of our eyesight may account for the many differences In the report! ot the same events in tho four Gospelc. all written by apostles who must have witnessed them or heard of them from eye-witnesses. An illustration of such variations Is to be found In the references In the Gospels to the "tranafiguratiem'1 of tho Snviour Three of the evangelists, St. Matthew. St Mark and St Luke, report this impressive occurrence, but St John, who appears to have witnessed i'. does not mention it. St. Matthew (chapter xvii.) says : "And after six days Jesus takcth Peter, Jame? and John his brother, and bringetb them up into an high mountain apart, "And was transfigured before them and his face did shine as the sun. and h',3 raiment rai-ment was white as the light " Why did not St. John observe and record that extraordinary occurrence? May It not have been because his perception for brightness, as the scientists express it. was b - ute than that of the other apostles? On tho other hand, in tho four accounts of the crucifixion in the Gospels, St. John slone mentions tho remarkable fact of tho Roman ?oldlcr striking the Saviour with a spear: "But one of the soldiers with a spear pierced his side, and forthwith came thero out blood and water." T!ii3 perhaps may be explained by the fact that St. John had a quicker eye for movement and contour in a vast confured than the other apostles, although his retinal centre for brightness may have been lei! acute than theirs. Th.-si are two conspicuous Illustrations of Important points which are mentioned by ono ovangelist and not by nnother. There are many others of more or less 1m-poriauce 1m-poriauce which have long been a subject of dit,uuasion and controversy among Bib- i - k ft 111 Wishes J : j i Various Typr$ of Ey?s Lovcr Than the Hum.m Eye. O) Vi&ual Cell of Enrth Worm, , , v " J Which Merelv DiBtin'-i'i-li:s B-twec-n Lirht And Dark. (2) Eye of Limpet, Which Per- . j ccives Only I'iotJon end Dirccljon. (3) Eye . ' v of Tubs. Worm, Which Perceives Orly ' -j Form. (4) Compound Eye of .- Fly, Which S65 Perceive. Onlv Verv Near Obiect. Jir' - ' v i r" leal scholars These are nil perhaps susceptible sus-ceptible of expadation by the new scientific scien-tific discoveries concerning tho mechanism of our eyesight. Experiments showed that in a group of rival objects ono person would see one object ob-ject and one another. Greater acutene?3 with one eye as compared with the other, greater contrast with the background, greater intensity and eye-movement, caused a predominance of one object over another. A great deal has been learned about eye-pight eye-pight through tho successful efforts to "camouflage" ships and military positions during the late war. Low visibility appears ap-pears to depend on brightness of background. back-ground. A certain amount of "glare " on the background would make an object practically Invisible. An ln?trument was made In accordance with this principle which was used in elaborate experimental tests made with model ships variously camouflaged. While army officers and artists were studying war camouflage they learned that the brain cen- -, f DHL : i i ti : I i &rv --rCTi rr-rj i I I n 111 i niinii piMw nw , , , ... image seen on I " " ' ' " ! i he r ' j,- T" pear to be what ' cxtcknml uirAce ti til" HbHIbBHH -4' , ; pacts or wishes ypfi" '" v'-'lj !" 'r'' 5w$ ' This peculiar- W S ': ' ' ntTlHt-PKruM. !,',." SO canioullago on Eg. , ""TAI-Cff ' ' I a n l V .aa'ef"'-' ,v- .'i2Lr''. Jf 1 ffcjS f I I make soldiers gK ' - V 'L;' ' ' I n d p.i'ifu: , -'l ; . v'i jj f in- ; ' 4 ng them tfI' & it- fk mummmmA 1 v.,!h -. f- Pt3S wr ground. How I flpr IS' "'V s - J v .j' CfO much this de- Lgjfr " CcM. ' 7S Pond eel ,.n y iCLfioTic " '' - VS inontnl In-,-- ;. ' A proved when it W 1"' . 1 U was found that Hm n nmmtmwmmmmmmKmmammmmmammnrr-i i m-rg- miiimhi mm - j the camera - Sy .' Tv '., 1 yV could 001 be Dijjjjram Showing How Every Image Ii Produced Upide Down on tho (. deceived like . ,.,.,r tn. ; U, 1 tliC eye When Bclina on Account of the Bcndinp of the Light Kayj in the Crystalline the observer's Lens. Various Part of the Retina Have the Function of Recording ' ! SB Color, F-rm, Detail and Motion, and These Functions Vary in Different merely a fallen perons. According to Which Function It Dominant, Ono I ' ih. trei trunk. Die ... . r- . j . ' J i Bmera would Pcrion, For Instance, Will Note Color and Ignoro Detail- , ) roveal Clearly While Another Will Only Note Detail and the outline of Ignore Color. I description by a war correspondent shows how camouflage camou-flage deceived the eye on land: "Spotted camouflage Is quite effective in breaking up the outlines ot any object. For Instance, in the case of large guns mounted on railroad carriages the usual camouflage consists ot a leopard-like coat of paint. Varle.Tated splotches of paint break up the stern lines of the gun so that at a dlstan-.o It melts info the surround) '.y landscape or si least appears as a mystifying, mysti-fying, shapeless mass. The spotted form of camouflage Is mostly employed where other means ace unavailable, and simple as It may seem It Is quite effective, according accord-ing to reports. "If it were not for the aerial camera camouflage would be a simple matter In so far as the airman Is concerned. But by decrees tho airman has perfected his photographic pho-tographic apparatus to a point where it tell6 him many things which would escape bis notice if he depended solely on his eyes." al sea the Idea of making a ship completely com-pletely Invisible to a submarine commander had to be abandoned. The method of mis leading and confusing the enemy by painting paint-ing the ship with cenain linc was devised Here again mental Interpretation of usual images was made use of. The .ship was painted so that she appeared ap-peared t; be going In a different course from her real one, and this led a submarine commander to lire his torpedo at the wrong lot. Queer, unusual lines painted errati- My on k ship's side ci.ught the enumy a so that ho could not follow her true i C i 10.0. tntcmatlon-x! Feature Serrlco. Inc. S&fi - ggs - outlines. A camouflage officer in the late war writes: m "Our scheme is to confuse the U-boat's range finder bv scrolls and curves In bright color?. A range-finder functions best when trained on an object presenting a solid mass, and tho disconcerting effect of a nightmare of color and shapes can be imagined im-agined by even the lay mlml. Certain color schemes tend to give the ship a shortened short-ened appearance, while others cause a funnel to disappear so that the Identity of the vessel Is hidden. In still other Instances In-stances a vessel Is painted so that a destroyer de-stroyer or U-boat appeurs to be alongside. "Then there is tho matter of determining a vessel's speed. In order to aim a torpedo the U-boat commander must know the approximate ap-proximate speed of his victim and its direction di-rection of travel, so that he can aim his torpedo some distance ahead and cause It to arrive at a predetermined point at the same time as the target Fake bow waves give the slow-moving freighter the earmarks ear-marks of an ocean greyhound." One of the most successful examples of marine camouflage was the painting of a large ship to look like a group of little ships going in different directions. This raised such a. complete confusion in tho eye of a submarine observor that ho was completely at a loss how to act. The ship was painted to look like threo small vo.i-m vo.i-m 1- going in one direction, while In the centre was painted tho bow of a fourth vessel looking as though it were going at right angles to the others. How completely the brain controls tho Great Britain Blbla Beaerrcxl. iigpE?5 The Remarkable EdisoHo nf tu. r the Side with Hia Spear I M 1 Soldier Striking the icur ia 1 Four EyangelbS De-crui th cT v nly by St Joh A-ough Al ; Why tho Other Three Ev. l J0"' The Pu"" n ; S Explained by the Facf That M J? Not M This May Be i , the Per? !SeWUMk Luke Ucked the Perception for detail. (N. appearance of what cno i aoothcr way. The lm S t,t'T'' P thrown PSJ0 d0. g '"""l" posiilen 0 lm',, ta Proper an7'u Zin 7 f naturo which gives us tho sen ' ot Vs" light." Jj Kcd light has tho effect of !r -: JJJ IH apparent size of an objcei. The uri sail E moon both appear larger al the borfco5 Hiw. than at the zenith. t c- tne apparent magnlfii itlon li s In'- Olor ussumed bv the ecl rising or setUng r. vV rd but a" objects on v- bori: which fall ,. idUi sometimes as greut as wotild result slon Is reduced or destroyed bv obserrUHl I |