The Age of Niagara Falls
The last word on this much-discussed subject, which is of great geologic importance, because the falls have been made to serve as a sort of standard by which all geologic time is measured, comes from J. W. Spencer, who concludes from the measured rate of recession during forty-eight years, together with other geologic data not usually taken into account, that the falls are thirty-one thousand years old, and the river thirty-two thousand; also that the Huron drainage was turned into Lake Erie less than eight thousand years ago. He thinks that the lake epoch began fifty thousand or sixty thousand years ago, and that the falls have about five thousand years more to live, at the end of which time the lake waters will discharge into the Mississippi.