Science, Geology and Physics 



bridge. One day we launched a small boat at the inclined rail- 1881 

 way, and entered on a most exciting and perilous exploration of 

 this part of the canon. The old guide long in charge of the 

 miniature ferry situated here accompanied the party. With 

 great difficulty we approached within a short distance of 

 the American Falls, which darted great jets of water upon us 

 and far out into the stream. The roar was so terrible that no 

 voice or human sound, however near we were to one another, 

 could be heard. The leadsman cast the line, which passed 

 rapidly down and told off eighty-three feet. This was quite 

 near the shore. Passing out of the friendly eddy which had 

 assisted us so near the Falls we shot rapidly down the stream. 

 The next cast of the lead read one hundred feet, deepening to 

 one hundred and ninety-three feet at the inclined railway. The 

 average depth to the Swift Drift, where the river suddenly becomes 

 narrow, with a velocity too great to be measured, was one 

 hundred and fifty-three feet. Just under the railway bridge the 

 whirlpool rapids set in, and so violently are the waters agitated 

 that they rise like ocean billows to the height of twenty feet. At 

 this point I computed the depth at two hundred and ten feet, 

 which was accepted as approximately correct. 



1882 



Madan, H. G. Complementary colors at the Falls of Niagara. 1882 

 (Nature. Dec. 21, 1882. 27:174.) Madan 



A letter to the editor of Nature regarding contrast-colors at the Falls. 



1883 



PoHLMAN, Julius. Life history of the Niagara river. Proc. A. A. 1883 

 A. S. (Aug. 1883. 32:302.) [Abstract.] Pohlman 



The author concludes that the " time necessary to excavate the gorge 

 of the Niagara below the falls has always been over estimated, for that 

 portion which would take the longest time — between whirlpool and 

 fall, was already excavated in pre-glacial times and the three miles between 

 whirlpool and Lewiston were composed almost entirely of shales." 



573 



