400 The National Geographic Magazine 



CERTAIN PERSISTENT ERRORS IN 

 GEOGRAPHY 



IT is strange that many legends which 

 a generation ago were accepted as 

 true, but which have long since been 

 disproved by geographers, should still 

 be accepted by the general public, and 

 even included in many geographic text- 

 books. Mr. Henry Gannett, in a recent 

 article in the Bulletin of the American 

 Geographical Society, enumerates a 

 number of these errors and shows 

 wherein they are at fault. 



It is a persistent idea that the pres- 

 ence or absence of forests has an influ- 

 ence upon the amount of rainfall. The 

 arid and desert regions of the world, 

 more particularly the shores of the Medi- 

 terranean Sea, have been cited as the 

 result of man's wanton destruction of 

 forests. In this case, however, the ab- 

 sence of forests is not the cause but the 

 result of the desert. The geographic 

 nature of the Mediterranean region, the 

 configuration of the land and water, and 

 the prevailing winds are of such nature 

 as to permit only of a Tight rainfall. 

 These conditions have existed for many 

 thousands and perhaps for millions of 

 years, and from the nature of the moun- 

 tains, cliffs, and cations of the region it 

 is apparent that they have been evolved 

 in a dry rather than in a moist climate. 



A second widespread error is that the 

 floods of our rivers have recently been 

 much greater and more frequent than 

 in former years, also due to destruc- 

 tion of the forests. The cutting away 

 of forests is usually, however, followed 

 by a thick growth of bushes and under- 

 brush, which holds the water as effect- 

 ively. Mr. Gannett cites the case of 

 the Ohio River as a proof that the floods 

 are not more frequent in recent years. 

 This river has been gauged continu- 

 ously, and the gaugings show very 

 little change. Whatever change has 

 taken place in the forest areas of its 

 basin. 



Another error is the citing the exist- 

 ence of fiords as a proof that the coast 

 has been sinking. These gorges are 

 partially filled by the sea, and it has 

 been argued that they must necessarily 

 have been cut when they were above the 

 sea-level. On the coast of Alaska we 

 now have similar fiords in the process of 

 formation by glaciers which at their 

 lower ends are often hundreds of feet 

 beneath the surface of the water. Un- 

 doubtedly the Norwegian fiords were 

 likewise cut by glaciers extending below 

 the surface of the water. The coast of 

 Norway may be sinking, but the fiords 

 are not evidence of it. 



Mr. Gannett believes that perhaps the 

 most prevalent error concerns climate. 

 It is generally believed that the mild 

 climate of Western Europe is produced 

 by the Gulf Stream, which washes its 

 shores ; that the severity of climate in 

 the northeastern part of the United 

 States is a result of a current from the 

 Arctic flowing along the coast, and that 

 the mild climate of Northwestern Amer- 

 ica is induced by the Japan Current, also' 

 sweeping down the coast. Each of these 

 beliefs is based upon the supposition of 

 a great body of water moving thousands 

 of miles in one steady stream. As a 

 matter of fact, both the Gulf Stream 

 and the Japan Current lose their velocity 

 long before they reach their supposed 

 destination, and the Arctic current is 

 proved not to exist. Mr. Gannett then 

 proceeds to explain the conditions of the 

 climate of these representative portions 

 of the earth as follows: The land ab- 

 sorbs heat rapidly and as rapidly gives 

 it off, while the water absorbs heat slowly 

 and holds its heat longer. The sea has 

 a much more uniform temperature be- 

 cause of its constant motion. The prev- 

 alent winds of the northwestern coast of 

 Europe blow from the sea, which is 

 warmer than the land in winter and 

 cooler than the land in summer; hence 

 the mildness of England's climate in 

 summer and winter. The prevalent 



