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SCIENCE 



[N. S. Vol. LII. No. 1354 



■witiiin two or three hundredths of a second 

 as to how much that clock is fast or slow. 



2. The accurate maps of the continents and 

 islands depend upon the astronomical deter- 

 minations of the latitudes and longitudes of 

 their salient features. 



3. The sailing of ships over long courses, 

 say from the Golden Gate to Sydney, Aus- 

 tralia, or from New York to the Cape of 

 Good Hope, depends upon the A B C's of 

 astronomy. Given fair skies the navigator 

 may locate his ship in the middle of the 

 broad ocean within a mile of its true position. 



4. In America it is the habit to call upon 

 the astronomers to fix the boundary lines 

 between nations, by observations of the stars; 

 for example, along the 49th parallel of lati- 

 tude, from Eainy Lake, Minnesota, westward 

 almost to the Pacific Ocean. The imcertainty 

 as to where this imaginary line falls upon the 

 ground is nowhere greater than ten or fifteen 

 feet, and it has not been foimd necessary by 

 us, nor by our friends in Canada, to main- 

 tain military forts along that line. 



5. The times of high and low tides, vital to 

 mariners in entering many harbors, are deter- 

 mined by or from the work of the astronomers. 



We do not dwell uiwn these responses to 

 the immediate needs of the world, for they 

 are unimportant in comparison with the con- 

 tributions of the pure knowledge side of 

 astronomy to progressive civilization. 



Let us think of the earth as etemall.y 

 shrouded in thick clouds, so that terrestrial 

 dwellers could never see the sun, the moon, 

 the comets, the stars, and the nebulse, but not 

 so thick that the sun's energy would fail to 

 penetrate to the soil and grow the crops. 

 Under these conditions we might know the 

 earth's surface strata to the depth of a mile 

 or two. We might know the moimtains and 

 the atmosphere to a height of four or five 

 miles. We might acquire a knowledge of the 

 oceans, but we should be creatures of exceed- 

 ingly narrow limits. Our vision, our life 

 would be confined to a stratum of earth and 

 air only four or five miles thick. It would be 

 as if the human race went about its work of 

 raising com for food and cotton for raiment, 



always looking down, never looking up, know- 

 ing nothing of the universe except an in- 

 significantly thin stratum of the little earth. 

 This picture is only a moderately imfair view 

 of life as it existed on our planet four him- 

 dred years ago, before the days of the tele- 

 scope, the spectroscope and the photographic 

 plate, before the days of freedom of speech 

 and thought, which came with the scientific 

 spirit. The earth is for us no longer flat, 

 supported on the back of a great turtle, which 

 rests upon nothing. It is round, and every 

 civilized person knows that it is. Exists 

 there an intelligent man in the world whose 

 thoughts, every day and many times a day, 

 are not unconsciously adapted to this fact? 

 This knowledge is a chief inheritance of the 

 new generations. It is fundamental in our 

 civilization. People know that the sun will 

 rise in the morning and set in the evening, 

 and why. A round earth, rotating upon its 

 axis in a dependable way and revolving 

 around the sun in exact obedience to law, are 

 truths incomparably more sublime than the 

 fiction of the flat earth which was pictured 

 hazily in men's minds during pre-Copernican 

 days. Who can estimate the value of this 

 knowledge to the human race? It can not be 

 expressed with the few figures which suffice 

 for the total of present-day financial trans- 

 actions. 



The stars are not lanterns hung out in the 

 sky by angels at night, but something in- 

 conceivably grander; they are suns, hundreds 

 of millions of suns, on the average com- 

 parable in size and brightness to our sun. 

 Is not this ascertained fact of nature a most 

 ennobling one to aspiring souls? Do not 

 these facts suggest and develop becoming 

 modesty in the minds of those who would 

 know the truth and pattern their lives in ac- 

 cordance with it? 



The following conversation occurred one 

 Saturday evening in the month of June, 1912, 

 at the eyepiece of the great telescope which 

 Mr. Warner and Mr. Swasey constructed and 

 erected for the Lick Observatory: I mention 

 the time, June, 1912, because it is of the 

 essence of the story. 



