190 GROVE KARL GILBERT— DAVIS [Mem0!KS [vouxx a i; 



popular article on the "Origin of the surface features of the United States" to the society's 

 Magazine in 1898, and he was of course selected to prepare an account of Niagara Falls in the 

 society's short-lived "National Geographic monographs," published in 1895. This excellent 

 account is referred to in another section; the previous article is of a muck more popular nature; 

 diastrophic processes of telluric origin are here called Plutonic, and erosional forces largely of 

 solar origin, Apollonic. The following extracts will illustrate the style of presentation here 

 employed: 



The Central Plain, comprising half of all the land [of the United States], has been shaped by Apollonic 

 forces. The geologist tells us of many uplifts, dislocations and flexures of the crust, but all these have been 

 reduced to approximate evenness by the cooperative work of rain, frost and rivers. Where hollows were made 

 they have been filled; where hills and mountains had grown they have been pared away, so that only their 

 roots, with a few low stumps, remain. . . . [In the Great Basin] the ranges are definitely Plutonic, each one 

 having been caused by a distinct local uplift. . . . Through extensive districts [of the same region] the alluvial 

 waste from the erosion and sculpture of the ranges is gathered in the intervening valleys, making of each one a 

 shallow basin or gently concave plain, where roads may run at will. Here and there some of the ranges are 

 almost buried by the alluvial filling, so that their summits project as craggy islands above a sea of rock waste.' 



Gilbert served as a manager of the Cosmos Club in Washington from 1890 to 1892, as its 

 vice president in 1893, and president in 1894. This appears to be the only instance in which 

 he accepted office in a nonscientific organization, if the Cosmos Club may be so called. There 

 is no record of bis having taken part, even as ordinary member, in any political organization or 

 in any society for public welfare; or of his having served on any paid or unpaid commission, 

 civic, State, or national; not that he was indifferent to good government and a better social 

 order, but that he did not directly concern himself in such matters. He was as nearly as possible 

 exclusively scientific in his activities. 



THE GEOLOGICAL SOCIETY OF AMERICA 



On the formation of the Geological Society of America, an organization which has come to 

 be second only to the national survey in its influence in American geology, Gilbert was listed 

 among its original members. He urged that the first councd of the society should be selected 

 with care, in order to secure a proper regulation of its affairs from the outset: 



The Society's publications should not be suffered to afford an asylum for inferior papers unable to secure 

 publication elsewhere. 



At the first winter meeting, held in New York City in 1889 under the presidency of the 

 venerable James Hall, he spoke on the "Strength of the earth's crust," a subject that is here 

 further discussed in a later section on "Isostacy" ; he was subsequently one of the most regular 

 and most highly valued attendants at the society's meetings for a number of years. An inci- 

 dent thoroughly characteristic of him is recalled from the New York meeting. Russell, report- 

 ing on a journey in Alaska, called attention to the prevalence of high and steep bluffs along 

 the right bank of the Yukon ; whereupon another member suggested that such bluffs might be 

 plausibly explained by the lateral erosion of the river under the influence of the earth's rotation, 

 which tended to deflect rivers to the right in the Northern Hemisphere with a force that 

 increased with the sine of the latitude and which should therefore be unusually effective in a river 

 in the high latitude of Alaska. Gdbert rose at once to make a correction, saying he desired to 

 point out that the deflective force did not increase with the sine of the latitude as the other 

 member had just asserted, but with the sine of twice the latitude, and that its maximum would 

 therefore be, not at the pole, but in latitude 45°. This statement caused consternation to the 

 previous speaker, who although confident of having correctly quoted the formula for the 

 deflective force, was at the same time fully aware of Gilbert's competence in the subject and wlio 

 had indeed had occasion previously to admire that competence as exhibited in his article above 

 noted on the "Sufficiency of terrestrial rotation for the deflection of streams " ; and he therefore, 

 on catching a glance from Gilbert as he sat down, expressed Ms consternation by a significant 

 movement of his closed hand, but said nothing further. Gilbert also remained silent until after 

 another paper had been presented, when he rose, saying: 



» Nat. Oeogr. Mag., iv, ix, 1898, 308-317; see pp. 312, 311. 



