MEMOKIAL OF CHARLES A. DAVIS 31 



which I started to inchide, but have omitted for brevity. I shall be glad 

 to show them to any one interested. 



Hardly had he finished his work on peat for the Micliigan Sur\'ey when 

 the call came to take np the same work in the wider fiehl of ilic United 

 States, in 1907. The family headquarters were removed to Washington, 

 but in the next few years Davis was all over the United States, cooperating 

 with various State surveys in their work on peat. 



The trip he made to the Great Dismal Swamp led to the recognition 

 of Lake Drummond as a type of lake which might develop in the forma- 

 tion of a peneplain, and be a sign not of youth, but of old age. After a 

 reconnaissance of the peat of the coastal plain clear way down to Florida, 

 the work in New York closely paralleled that of Michigan ; but when in 

 1907 to 1909 the work of peat investigation began in Connecticut he 

 found fresh-water peat below salt-water peat, and thus liis attention was 

 called to that evidence of subsidence or submergence along the Atlantic 

 coast, to which he has added so materially. He clearly saw the real point, 

 not that there has been oscillations of the strand both up and down since 

 the ice age — this no one denies — but there is now going on a submergence 

 of the land around Boston at such an appreciable rate as a foot a century. 

 It was Davis' service that he pointed out the lines of investigation wlvich 

 might indicate not merely submergence sometime, but present and con- 

 tinuous — investigations which have been answered only by assuming that 

 the submergence is relative to the liigh tide level, and that this has grown 

 greater, while the general average sealevel has not changed. On liis work 

 in this direction not many letters are needed, as this Society has already 

 published notes about it. 



In his studies of seacoast sul)sidence, 1910 to lOlfi, he lias acted as 

 protagonist of the botanists and believers in subsidence against D. W. 

 Johnson, who is equally imbued with the scientific spirit and with Whom 

 his personal relations were most friendly. To be sure, Davis, like the 

 rest of us, sought for facts on that side of the case whicli lie favored. 



Those of us who were at the New England intercollegiate excursion of 

 1911 will remember the debate between Davis and Johnson on tlie Med- 

 ford marshes, where the salt-water peat SM^athes great pine stumps grow- 

 ing in place, lasting until the moon rose and we "felt the damp of the 

 river fog that rises Avhen the sun goes down.'' But not so many know 

 that, inspired by that discussion, during the excursion Davis thought of 

 the railroad cinders in the peat as a measure of the ui)growth of the 

 variety of peat formed almost wholly of plants that only grow at extreme 

 high tide level and slipped off with his sampler and brought l)ack before 

 the close of the excursion and discussion samples that showed the up- 



TTI — Bull. Geol, Soc. Am,. Vol. .28. 1916 



