2io THE POPULAR SCIENCE MONTHLY. 



here represented in profile can be traced from 30 to 130 miles, running 

 into Indiana. Toward the north, in Michigan, they unite by conver- 

 gence, but one or two being visible in that State. Another article will 

 treat the interesting question of the origin of the drift. 



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SOME OBSERVATIONS ON NIAGARA. 1 



Br Prof. JOHN TYNDALL, IX. D., F.K.S. 



IT is one of the disadvantages of reading books about natural 

 scenery that they fill the mind with pictures, often exaggerated, 

 often distorted, often blurred, and, even when well drawn, injurious to 

 the freshness of first impressions. Such has been the fate of most of us 

 with regard to the Falls of Niagara. There was little accuracy in the 

 estimates of the first observers of the cataract. Startled by an exhi- 

 bition of power so novel and so grand, emotion leaped beyond the 

 control of the judgment, and gave currency to notions regarding the 

 water-fall which have often led to disappointment. 



A record of a voyage in 1535, by a French mariner named Jacques 

 Cartier, contains, it is said, the first printed allusion to Niagara. In 

 1603 the first map of the district was constructed by a Frenchman 

 named Champlain. In 1648 the Jesuit Rageneau, in a letter to his 

 superior at Paris, mentions Niagara as " a cataract of frightful height." 2 

 In the winter of 1678 and 1679 the cataract was visited by Father 

 Hennepin, and described in a book dedicated " to the King of Great 

 Britain." He gives a drawing of the water-fall, which shows that 

 serious changes have taken place since his time. He describes it as 

 " a great and prodigious cadence of water, to which the universe does 

 not offer a parallel." The height of the fall, according to Hennepin, 

 was more than 600 feet. " The waters," he says, "which fall from 

 this great precipice do foam and boil in the most astonishing manner, 

 making. a noise more terrible than that of thunder. When the wind 

 blows to the south, its frightful .roaring 'may be heard for more than 

 fifteen leagues." The Baron la Hontan, who visited Niagara in 1687, 

 makes the height 800 feet. In 1721, Charlevoix, in a letter to Madame 

 de Maintenon, after referring to the exaggerations of his predecessors, 

 thus states the result of his own observations : " For my part, after 

 examining it on all sides, I am inclined to think that we cannot allow 

 it less than 140 or 150 feet" a remarkably close estimate. At that 

 time, viz., a hundred and fifty years ago, it had the shape of a horse- 

 shoe, and reasons will subsequently be given for holding that this 



1 A lecture before the Royal Institution, delivered April 4, 1873. 



2 From an interesting little book presented to me at Brooklyn by its author, Mr. 

 Holly, some of these data are derived : Hennepin, Kalm, Bakewell, Lyell, and others, I 

 have myself consulted. 



