﻿part 1] awstiveksah r .iddeess oe the president. 



had published his pioneer volume on the Geology of Brazil in 

 1870. After graduating in 1873, Dr. Derby became Assistant 

 to Prof. Hartt, who had just been appointed Director of an 

 Imperial Geological Commission of Brazil ; and in the following 

 year he went to Rio de Janeiro to act as Assistant in the con- 

 templated survey. On the death of Hartt in 1878 the work 

 of the Commission ceased, and in 1879 Derby was made chief 

 of the geological section of the National Museum of Rio de Janeiro. 

 The most important of his early memoirs on the Region of 

 the Lower Amazons, the Cretaceous Basin of Bahia, and the 

 Diamantiferous Region of the Parana, were published in the 

 'Archivos' of the Rio Museum in 1877 and 1878. In 1886 

 Derby left Rio and became Director of the Geographical and 

 Geological Commission of the State of Sao Paulo, where he 

 remained until 1905. He then undertook an examination of 

 the diamond-bearing rocks of the State of Bahia, and shortly 

 afterwards returned to Rio as Director of a new Geological and 

 Mineralogieal Survey of Brazil, which he carried on energetically 

 until his lamented death. In 1887 and 1891 Derby contributed 

 two papers on the nepheline-rocks of Brazil to the Quarterly 

 Journal of the Geological Society. He was especially interested 

 in petrology and in the occurrence of accessory minerals in rocks, 

 and published many papers in the ' American Journal of Science ' 

 and in the ' Journal of Geology,' which are not only of scientific 

 importance but of economic value. At the same time, he did 

 not neglect airy aspect of the science ; and one of his latest papers 

 was devoted to an exhaustive study of the stem of the Permo- 

 Carboniferous plant, Psaronins hrasiliensis. 



Derby was an attractive personality, full of enthusiasm for his 

 science, and always eager to welcome geologists who visited the 

 land of his adoption. He gave special help and encouragement to 

 Prof. J. C. Branner during his numerous researches in Brazil, and 

 he similarly aided Dr. I. C. White in the preparation of his 

 monumental volume on the coal-bearing rocks of Rio Grande 

 do Sul. He was also associated with our Fellow, Mr. Joseph 

 Mawson, when he was resident in Brazil and devoting attention 

 to the geology of the country. In 1896, and again in 1907, I had 

 the pleasure of experiencing his welcome both in Rio de Janeiro 

 and in Sao Paulo, and learned to appreciate the difficulties 

 under which he pursued his work with a strangely unsympathetic 

 Government. He was elected a Fellow of the Geological Society 



