108 PROCEEDINGS OF THE ALBANY MEETING 



ment for investigations on Panama, with instructions to report to General 

 Goethals. Though he was able to devote only a month to this work, yet 

 this sufficed for him to grasp the salient features of the problem. In a 

 brief report he pointed out the causes of the landslides which were then 

 threatening the Culebra Cut and suggested means for overcoming the 

 difficulties. Hayes also outlined a plan for further investigations and 

 recommended continuous observations as the work progressed. The prin- 

 ciples he announced relating to the causes of the slides have been verified 

 by all subsequent investigators. 



Hayes made one other geologic excursion into the Caribbean region. 

 At the second occupation of Cuba, General Wood, Military Governor, 

 owing to a suggestion of Dr. David T. Hay, made a request for a geologic 

 reconnaissance of the island with the purpose of determining its mineral 

 resources. Hayes was detailed in charge of this work in 1901, assisted 

 by T. Wayland Yaughan and Arthur C. Spencer. Hayes was able to 

 devote only five weeks to the field-work, while his assistant spent some 

 three months in Cuba. Before the end of the year a report on the geology 

 and mineral resources of Cuba — the first of its kind — was submitted. 



Economic Geology 



During the first six years of his professional work Hayes devoted rela- 

 tively little time to the study of mineral deposits. When in 1893 the 

 modern epoch of the National Survey's activity in economic geology be- 

 gan, it fell to Hayes to study the Tennessee phosphates, and in the fol- 

 lowing year the bauxite deposits of the South. In this field he made his 

 first direct application of chemistry, to the study of which he had devoted 

 so many years of his life. As was to be expected, he soon became the 

 leading authorit}' on the occurrence of bauxite and phosphate. 



In his description of these deposits he presented not only the facts and 

 interpretations in regard to occurrence and origin, but also made quanti- 

 tative estimates of reserves. His was, therefore, among the first reports 

 of the Federal Survey to treat of mineral resources in a quantitative way. 

 Later, when under the stimulus of the conservation movement, a census 

 of the mineral deposits of the country was called for, he was far better 

 able to supervise the work in his capacity of Chief Geologist, because it 

 was but an extension of his own work. 



The importance of Hayes's work in economic geology, as well as his 

 administrative ability, was lecognized in 1900 by placing him in charge 

 of the newly organized section of non-metalliferous resources. For the 

 next five years Hayes continued to give personal supervision to this work 

 in spite of the fact that he liad meanwhile assumed other heavy admiiiis- 



