18 PROCEEDINGS OF THE WASHINGTON MEETING 



During the last eight years Derby has given much of his time to the 

 study of Psaronius and its relationships. The last of his published papers 

 was on the stem structure of Tietea singularis, which appeared in the 

 American Journal of Science for March, 1915, pages 251-260. 



Having to undertake work in regions hut poorly supplied with maps, 

 one of his first and most important duties, when he becamo State Geologist 

 of Sao Paulo, was the inauguration of topographic work. This work was 

 intrusted to Horace E. Williams, an able and energetic young American, 

 to whom the State of Sao Paulo and the scientific world are indebted for 

 an excellent series of topographic maps, on a scale of 1 to 100,000, to 

 say nothing of his explorations of the western portions of that State, his 

 work on tire Serra da Canastra, etcetera. 



Derby's own list of publications on the geology of Brazil numbers 125 

 papers. Naturally they embrace a. wide range of subjects. Ten of his 

 papers relate to the geology and genesis of the Brazilian diamonds. He 

 became interested in the early cartography of Brazil and published a 

 number of papers on the subject. 



As an author and as a scientific reasoner, he was an extremely cautious 

 man, so much so that the word "hedge" was constantly on his lips, both 

 for his own guidance and as a. warning to his assistants. 



The last evening I spent in his rooms at Rio de Janeiro he referred to 

 this personal trait and remarked that it had prevented his marrying; that 

 he was too cautious to take the risk. This cautiousness of his was prob- 

 ably the real reason for some of the long delays in publishing his results, 

 which led to tire tying up of his own results and those of his assistants. 

 Without doubt he hoped the delays would enable him to put everything 

 beyond question and to make his reports final and complete instead of 

 preliminary and tentative. But the delays were prolonged from year to 

 year, until his assistants became discouraged and the government more or 

 less exasperated at the lack of practical results for such great and long 

 continued expenditures. It was largely this long delay that finally led 

 to his resignation as State Geologist of Sao Paulo. 



Derby never felt obliged to show results. After he had been State 

 Geologist of Sao Paulo for ten or twelve years and had published next to 

 nothing on the geology of that State, I asked him point blank and with 

 some feeling where his results were. He replied : "They are in my head." 

 We had to change the subject. But the important fact behind his delays 

 is that the geology of Sao Paulo is difficult and involves problems that he 

 had not been able to settle to his own satisfaction, and he was unwilling 

 to commit himself to paper and thus lay himself open to adverse criticism. 



It seemed unfortunate for Brazil, for himself, and for the cause of 



