mile to the deepest deplli in an ocean, tlic I'acitk, 320S8 feet, tlic distance is 

 over WOO miles. From W'asiiin^'ton. D. C".. to the liij;hest heifjiit on the (ilohc, 

 Mount i'".verest, 29,002 feet, the distance is more than 9000 miles. Kroin the 

 deepest depth in an ocean to the highest heij;h on the (liobe, there is an alti- 

 liide of 61,090 feet. ll/i miles. If we rcmov our '"150 pound man" from tiie 

 Karlh's centre and place him at the very bottom of the Pacific Ocean, his body 

 will be under the terrific pressure of at least 1.^500 tons. If we iilace this man 

 upon the sunnnit of Mount Everest, he would then be undL-r a pressuie of np- 

 [iroximalely only 5 tons. 



A cubic foot of sea water has a weight of 64.3 pounds, and, accordin^'ly. wc 

 should not be surprised that a man's body, placed at the very bottom of the 

 Pacific (\x'an, .U,000 feet below its surface, would be crushed to a pulp by tlie 

 pressure of water. At the surface of the sea there is an atmosplieric pressure 

 of 14,7 pounds upon every one of the 2000 square inches covering a human 

 body, so that there our "150 pound man'' would be surrounded by a total indi- 

 vidual pressure of more than 14 tons. Fortunately, however, this exterior pres- 

 sure inward is counteracted and neutralized by an equal interior pressure out- 

 ward, for, otherwise, our bones would have to be stronger and harder to resist 

 the atmospheric pressure. This atmospheric pressure becomes less and less as 

 we ascend abo\'e sea level, and it is probable that the terrestrial atmosphere does 

 not extend higher than 300 miles. llowe\'er, our atmosphere approximates a 

 volume of 60 billion cubic miles and a total weight of almost 6 quadrillion tons. 



If we were able to ascend above our atmosphere and escape from the Earth, 

 we should experience another interesting fact. It has already been stated that 

 if we could descend far below the terrstrial surface, we should lose "weight" 

 directly as the distance. That is, at one-fourth of the distance of the ter- 

 restrial centre, we should weigh only three-quarters of what we did at the .sur- 

 face, at one-half of the distance only one-half, and at the very centre we should 

 possess no weight at all. Now, if we were able to ascend far above the ter- 

 restrial surface, we should find that we lose weight according to the square of 

 the distance, in\'ersely. Since the distance from Earth's surface to its centre 

 is about 4000 miles, then if our "ISO pound man" could ascend 4000 miles 

 aobve that surface, he would weigh only ^th as much as he did at the surface. 

 For. having ascended 4000 miles, he would be twice as far as he was from the 

 terrestrial centre, inasmuch as 8000 miles are twice 4000. Therefore, he would 

 weigh /4th of of 150 pounds, or 37^/2 pounds. If he rose 8000 miles above the 

 terrestrial surface, he would be 12,000 miles from the terrestrial centre, thrice as 

 far, since 12.000 miles are thrice 4000, and, accordingly, he would weigh l/9th 

 of what he did, or 16 2/3rds pounds. Moreover, if he left the Earth 240,000 

 miles behind him, he would still possess some weight. This distance would be 

 60 times the Earth's radius, and, therefore, his weight would be diminished to 

 1 /3600th of his terrestrial weight — a little more than 4/lOOths of a pound. 

 Now 240.000 miles are about the mean distance of our Earth from its Moon, 

 and it is evident that 4 /100th of a pound, about 2/3rds of an ounce, represent 

 the influence of terrestrial gravity upon our "150 pound man," were he placed 

 on the lunar surface. 



There are many, many more Interesting facts about our Planet, many of 

 which are discovered "under the microscope." One of these other facts is dis- 

 covered "through the telescope," — the indescribable minuteness of our Earth 

 compared with the Indescribable vastness of the Universe. Our own "local Uni- 

 verse" is bounded by the so-called "Milky Way," and the distance across it, the 

 diameter of the "Milky Way," has been variously estimated, one of these esti- 

 mates approximating 6 quadrillion miles. If this estimate is correct, our planet, 

 compared with our "local Universe," resembles a veritable pea situated within a 

 circular area, an area so vast that it would take an aeroplane speeding 100 miles 

 an hour approximately 70 million centuries to fly across it! 



