390 Eininent Living Geologints — 



Darwin used to invite Judd from time to time to meet him and 

 discuss current geological topics. Scrope, at this period too old and 

 infirm to undertake further travels, sent Judd to visit the diiierent 

 volcanic districts of Europe, vsrhich he himself knew so well, aiding 

 him the while by conversation and correspondence. Never surely 

 was young geologist so fortunate and happj"^ in securing the friend- 

 ship and teaching of men like Lyell, Darwin, and Scrope ! 



As the results of his travels over Europe, Judd published a series 

 of papers under the title of " Contributions to the Study of 

 Volcanoes." He also read before the Geological Society a paper 

 on the ancient volcano of Schemnitz. In his earlier memoirs he 

 had been content to adopt Bunsen's classification of rocks in an Acid 

 and a Basic series. He now, however, showed that such a simple 

 classification was beset with difficulties, and proposed the term 

 " Intermediate " for that extensive class of rocks which could not 

 be conveniently assigned to either of Bunsen's classes. The French 

 geologists, later, adopted the same plan, calling the intermediate 

 rocks " Neutral." At a later date Judd proposed the separation of 

 the smaller group of " Ultrabasic rocks" as a distinct class. His 

 study of the contemporaneous volcanic rocks of Bohemia and Hungary 

 led to the recognition of the fact that a geographical distribution of 

 rocks exists, not less marked than that of animals and plants, and 

 this idea crystallized in the suggestion of the term " petrographical 

 province," which is now so universally adopted. While travelling 

 over the volcanic districts, Judd was able to send to his friend 

 Professor Story Blaskelyne large collections of rock-specimens, 

 which were deposited in the Mineral Department of the British 

 Museum. 



During his journeys upon the Continent for the purpose of 

 studying the volcanic rocks, Judd never lost sight of the importance 

 of making himself acquainted with the best methods of teaching 

 science. His frequent intercourse with his former teacher and 

 constant friend — Professor Huxley — had led him to recognize the 

 supreme value of practical teaching in science, and, while visiting 

 the various universities and mining schools of the Continent, this 

 point was kept constantly in view. In 1876 the opportunity of 

 taking up the teaching of geology arrived, through the resignation 

 by Sir Andrew Ramsay of the professorship of geology in the Eoyal 

 School of Mines on his appointment to the Directorship of the 

 Geological Survey. By the unanimous vote of the Council Judd 

 was recommended for the vacant post, and at once entered on its 

 duties. 



After lecturing for a year at Jermyn Street, it was found that the 

 impossibility of obtaining laboratory accommodation necessitated the 

 removal of the geological division to South Kensington, to which 

 place most of the other divisions of the school had already been 

 transferred, and in 1881 the sphere of work of the school was 

 enlarged by the creation of the Royal College of Science. Here, 

 with the assistance of Huxley, Judd organized a system of practical 

 teaching in geology, similar to that already established for biology. 



