MEMORIAL OF E. W. HILGARD 53 



geological report (I860), he devoted half of the report to the geology 

 and half to the soils in their various relations — that is, to agricnltnre. 



Since the soils are derived from preexisting rocks, the study of these 

 rocks must precede the discussion of the soils derived therefrom. Doctor 

 Hilgard has recognized this, and the accuracy and thoroughness with 

 which he has described the geological formations of the Mississippi em- 

 bayment are evidenced by the fact that subsequent work of geologists in 

 this region, while adding details and filling out some of the outlines laid 

 down, has not necessitated any fundamental cliange in the geology as 

 depicted by Hilgard in his 1860 report and in his published essays. 



As Professor Wickson has said in this connection, Hilgard has demon- 

 strated his power in research and exposition by exalting the State of 

 Mississippi into the first rank of the States wliich knew their geology to 

 the very bottom of it, and has advanced Mississippi even beyond others 

 of its rank by tracing its soils to the rocks whence they came by ice, wind, 

 and water. 



His outlining of the great Mississippi embayment and his recognition 

 of the axis of this embayment as a line of maximum oscillation in late 

 Tertiary and early Quaternary times and his explanation of the accumu- 

 lation of Grand Gulf and Lafayette sediments in connection with these 

 oscillations must stand to his credit in any estimate of his purely geolog- 

 ical work. His recognition of the Cretaceous ridge or backbone of Louisi- 

 ana and its connection with salt, sulphur, and petroleum, occurrences was 

 an achievement of the first importance, as was also his study of the 

 exceptional character of the Lower Mississippi delta, and of the mud 

 lumps, which brought recognition from the National Academy of Sciences, 

 as he has stated above. 



Through all this purely geological work, which of itself would have 

 placed Hilgard in the foremost rank of the geologists of his day and 

 generation, the thought of the soil, its nature and characteristics, its 

 relation to forest growth and to cultivation, dwelt constantly in Hilgard's 

 mind, as may be seen in the prominence given to it not only in his first 

 report and in his published articles before he went to California, but also 

 in his numerous official reports of the Department of Agriculture of the 

 University of California. 



The chemical analyses of the soils considered in connection with their 

 physical properties, their natural forest vegetation, and the corresponding 

 cultural experience have been consistently carried out by him, as else- 

 where stated, with the result of establishing their utility in the a priori 

 determination of their adaptation, permanent value, and best means of 

 cultural improvement. 



