Chapter 21
Gravity. The force of gravity, unscientifically speaking, is the influence which one body has upon another commonly known as attraction. All material substances attempt to draw others to them, and the larger the substance, the greater its attractiveness or drawing power. The earth, being larger than anything near it, draws everything to it. A ball thrown into the air
returns to the earth as soon as the force which propelled it upward is exhausted. If the ball were larger than the earth, the earth would move toward the ball, or rather each would move toward the other, but the smaller body would go the greater distance. The entire universe would, undoubtedly, come together in one solid mass if the bodies were not held apart by laws and energies, which are not yet fully understood by men. Sir Isaac Newton discovered the action of gravity,
but no one knows exactly what it is. Great American Inventions. The following list of fifteen Great American Inventions is taken from Killa Kelly's Curious Questions. 1. The Cotton Gin. 2. The Planting Machine. 3. The Grass Mower and Reaper. 4. The Rotary Printing Press. 5. Steam Navigation.
6. The Hot Air Engine. 7. The Sewing Machine. 8. The India Rubber Industry. 9. The Machine Manufacture of Horseshoes. 10. The Sandblast for Carving. 11. The Gauge Lathe. 12. The Grain Elevator. 13. Artificial Ice Making on Large Scale. 14. The Electric Magnet and its Practical Application. 15. The Telephone.
Great Eastern. The Great Eastern was, in her time, the largest vessel in the world, but would be considered small compared with the giant ocean liners of today. She was built in London and launched in 1858. She cost $300,000. She had a length of 680 feet, breadth of 82.5 feet or 118 feet including the paddle boxes, and a height of 58 feet. Her motive power consisted of eight engines with a total of 11,000 horsepower.
She was slow and unwieldy and was not a success except for the laying of the Atlantic Cable. Great Libraries. The Congressional Library, Washington, contains 1,800,000 volumes. Boston Public Library and New York Public Library, each 900,000. Harvard University Library, 800,000. New York State Library, 520,000. Yale University Library, 400,000. Bibliotheque Nationale, Paris, 2,600,000. British Museum, London, 2 million.
Imperial Publinaia Bibliotheca, St. Petersburg, 1,330,000. Koniglichi Bibliotheca, Berlin, 1,200,000. Konehof U. Staatsbibliotheca, Munich, 1 million. KUK Hofbibliotheca, Vienna, 900,000. Great Tunnels. The Arlberg Tunnel under the Alps is 6 ¾ miles long. The Gunnison Tunnel in Colorado is 6 miles long. The Hussack Tunnel in Massachusetts is 4 ¾ miles long. The Mont-Sinus in Italy and France is 8 miles long.
The New Croton Water Tunnel in New York is 33 ¾ miles long. The O'Teara in New Zealand is 5 ¾ miles long. The tunnel which drains the Freiburg Mine Saxony is 31 ¼ miles long. The St. Clair Tunnel connecting Sarnia, Ontario with Port Huron, Michigan is 2 miles long. The St. Gotthard Tunnel in the Alps is 9 ¾ miles long. The Strawberry Tunnel in the Wasatch Mountains is 50 miles long. End of Section 21
