737 



SCIENTIFIC SIDE-LIGHTS 



Victory 



Vision 



creation, and which we have discovered to 

 be worlds in magnitude, are not also worlds 

 in use and in dignity ? Why should we think 

 that the great Architect of Nature, supreme 

 in wisdom as he is in power, would 

 call these stately mansions into existence 

 and leave them unoccupied? When we cast 

 our eye over the broad sea, and look at the 

 country on the other side, we see nothing 

 but the blue land stretching obscurely over 

 the distant horizon. We are too far away 

 to perceive the richness of its scenery, or 

 to hear the sound of its population. Why 

 not extend this principle to the still more 

 distant parts of the universe? What tho, 

 from this remote point of observation, we 

 can see nothing but the naked roundness 

 of yon planetary orbs? Are we therefore 

 to say that they are so many vast and un- 

 peopled solitudes; that desolation reigns in 

 every part of the universe but ours; that 

 the whole energy of the divine attributes is 

 expended on one insignificant corner of these 

 mighty works; and that to this earth alone 

 belongs the bloom of vegetation, or the 

 blessedness of life, or the dignity of rational 

 and immortal existence? CHALMERS Astro- 

 nomical Discourses, p. 21. (R. Ct., 1848.) 



3651. 



Stars Seem to Re- 



volve around the Pole The " Steadfast Po- 

 lar 8 tar " Changes Place in the Sky, If we 

 w r atch the heavenly bodies for a few hours 

 we shall always find them in motion, those 

 in the east rising upwards, those in the 

 south moving towards the west, and those in 

 the west sinking below the horizon. We 

 know that this motion is only apparent, 

 arising from the rotation of the earth on 

 its axis; but ... we may speak of the 

 motion as real. A few days' watching will 

 show that the whole celestial sphere seems 

 to revolve, as on an axis, every day. It is 

 to this revolution, carrying the sun alter- 

 nately above and below the horizon, that 

 the alternations of day and night are due. 

 The nature and effects of this motion can 

 best be studied by watching the apparent 

 movement of the stars at night. We should 

 soon learn from such a watch that there is 

 one point in the heavens, or on the celestial 

 sphere, which does not move at all. In our 

 latitudes this point is situated in the north, 

 between the zenith and the horizon, and is 

 called the pole. Around this pole, as a fixed 

 center, all the heavenly bodies seem to re- 

 volve, each one moving in a circle, the size 

 of which depends on the distance of the 

 body from the pole. There is no star situ- 

 ated exactly at the pole, but there is one 

 which, being situated little more than a de- 

 gree distant, describes so small a circle that 

 the unaided eye cannot see any change of 

 place without making some exact and care- 

 ful observation. This is therefore called the 

 pole-star. . . . The altitude of the pole 

 is equal to the latitude of the place. NEW- 

 COMB Popular Astronomy, pt. i, ch. 1, p. 9. 

 (H., 1899.) 



3652. VISION, BINOCULAR The Ef- 

 fect of Seeing with Two Eyes. In Nature 

 we see every object with two eyes, each of 

 which occupies a somewhat different stand- 

 point in space. We therefore acquire two 

 pictures of each separate object that we 

 blend in our conception into one physical 

 whole. That is why we see objects in Na- 

 ture in so much greater relief than in paint- 

 ing. KAAT Leonardo da Vinci als Natur- 

 forscher. (Translated for Scientific Side- 

 Lights.) 



3653. VISION, DEFECTIVE Color- 

 blindness Case of Dr. Dalton. The most 

 interesting case of [color-blindness] is that 

 of the celebrated chemical philosopher, Dr. 

 Dalton, of England. He published an ac- 

 count of his own case and that of several 

 others in the Transactions of the Manches- 

 ter Society in 1794. Of the seven colors 

 of the rainbow he could distinguish but two, 

 yellow and blue; or at most, three, yellow, 

 blue, and purple. He saw no difference 

 between red and green; so that he thought 

 the color of a laurel leaf the same as that 

 of a stick of red sealing-wax. A story is 

 told of his having, on one occasion, appeared 

 at the Quaker meeting, of which he was a 

 member, in the usual drab coat and small- 

 clothes of the sect, with a pair of flaming 

 red-colored stockings to match. Whatever 

 may be the truth in reference to this story, 

 we have the assertion of Professor Whewell 

 that when Dr. Dalton was asked with what 

 he would compare the scarlet gown with 

 which he had been invested by the univer- 

 sity, he pointed to the trees, and declared 

 that he perceived no difference between the 

 color of his robe and that of their foliage. 

 HENRY Color Blindness (Scientific Wri- 



9, vol. i, p. 236). (Sm. Inst., 1886.) 



3654. VISION INDEPENDENT OF 

 ARGUMENT OR CALCULATION Appar- 

 ent and Real Size of Church Clock and Ball 

 on Steeple. Vision requires to be convinced 

 [through its own organs]. No assertion on 

 the part of other people, no speculation or 

 calculation is of influence in determining 

 our perception, but only an association of 

 ideas repeated over and over again. Isolated 

 experiences, therefore, make no impression 

 upon our minds. From a window in my 

 room I look directly upon a neighboring 

 church tower. The face of the church clock 

 appears about as large as that of a moder- 

 ately large clock which hangs upon my wall. 

 The ball of the steeple looks about as large 

 as the button of a flagstaff. A little while 

 ago the clock face and steeple knob were 

 taken down for repairs and lay upon the 

 street. To my astonishment, I saw that the 

 former was as large as a church door, and 

 the latter as large as a wagon-wheel. Now 

 the two are in their places again and look 

 to me just as they did before, altho I have 

 learned their true size. The workman upon 

 the roof does not seem so much smaller 

 than he actually is, because I have observed 



