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Natural History: Frequently revised and brought up to date, they remained standard texts in English and American schools for nearly a century, as did his 8-volume History of Earth and Animated Nature (1774), a survey of natural history drawn from many sources, but enlivened and enriched by his own observations.
Natural and Man-made Glass.—The origin of the invention or discovery of glass is lost in the mists of time. As a natural product, looking like common stones and distinguished from them only by its brilliance, glass was scattered around the volcanic areas of the earth, having been fused by nature in her volcanic fires. This natural glass is known as obsidian. Man-made glass did not begin its progress until many centuries after the beginning of recorded history.
Transportation routes tend to be direct straight lines between any two traffic centers, unless there are such obstacles as mountains or bodies of water, or unless it seems worthwhile to deviate from the straight line to serve an intermediate trade center. Ocean routes are deflected by land masses. Of all modes of transportation, the most modern, air transportation, is least affected by topography or other natural conditions in following a straight-line route.
The present article provides a general survey of transportation under the following main headings:
1. History 3. Influence of Transportation
2. Factors in the Develop- on History
ment of Transportation 4. Bibliography
1. History |
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