338 



THE LAKE GEORGE SENKUNGSFELD, 



The graph (fig. 4) is drawn from that given in Russell's paper 

 (quoted above), and brought up to date from information given 

 me by Mr. Glover, who keeps an official record of the meteorology 

 of Lake George. 



vi. Age of the Subsidence. 



Mr. Russell made use of Lake George as a gigantic rain-gauge, 

 and, from the data he obtained, he put forward some ver}' inter- 

 esting theories as to weather cj'-cles and their causes. It has 

 occurred to me that Lake George may serve as a geological 

 chronometer for much the same reason, that it " keeps all it gets," 

 whether water or silt. The foregoing sections will demonstrate 

 the reasonability of stating that Lake George probably never had 

 an outlet. Hence the silt deposited in Lake George should give 

 us some idea of the time which has elapsed since the extensive 

 faulting instanced took place. 



All the data made use of are open to criticism, but it is hoped 

 that the method used may be of interest, and that the result may 

 represent a period of years of the right order if not correct to a 

 few hundred units. 



From Russell's textbook on Rivers* I obtained the following 

 figures for the silt-deposits of the River Po in North Italy; and 

 corresponding numbers for Lake George are tabulated alongside. 



Table i. 



A. (Area) gives the amount of material to be acted on. 



B. (Rainfall) gives the effective eroding agent. 



* River-Development. By I. C. Russell, 1898, pp. 74-5. 



