SKETCH OF JAMES CROLL. 551 



Having completed Climate and Time, Dr. Croll desired to 

 abandon the study of climatology and physics in order to engage 

 in the investigation of the philosophy of evolution preparatory 

 to a work on that subject which he contemplated. But his book 

 had become a topic of general discussion in which he was obliged 

 to participate, to the extent at least of seeing that his views were 

 correctly quoted and understood ; and consequently he still pub- 

 lished articles and wrote much in correspondence on subjects 

 treated in it. During the summer of 1880 he suffered a strain in 

 the region of the heart which almost completely disabled him. 

 Making an external application of aconite, under his physician's 

 advice, to the seat of the pain, he lost the power of speech tem- 

 porarily, and contracted an impediment in utterance which did 

 not disappear for several years. He finally thought it his duty 

 to resign his position on the Geological Survey, and accordingly 

 retired from the Government service in the spring of 1881. Ap- 

 plication was made by his friends for a liberal pension, corre- 

 sponding with the merits of his work, under the superannuation 

 act ; but although the Government dealt at the time with consid- 

 erable liberality with other persons whose deserts were no greater 

 than his, an allowance of 100 from the Queen's bounty and a 

 superannuation allowance of 75 16s. Sd. a year were all that 

 were granted him ; and although repeated applications were made 

 on various aspects of the case, and backed by what would appear 

 to be among the most influential names in the kingdom, no more 

 could be got. 



Among the first fruits of Dr. Croll's new studies was the 

 article on Evolution by Force Impossible ; a New Argument 

 against Materialism, which was published in the British Quarterly 

 Review for January, 1883. It was a discussion of the question of 

 " What determines molecular motion and force ? " and an attempt 

 to prove that force alone, motion alone, or any sort of act alone, 

 that is, undetermined to any particular direction, is unable to ac- 

 count for evolution. If his conclusion were correct, it would 

 follow that Mr. Spencer's theory of evolution by force was abso- 

 lutely impossible. A copy of this article was sent, with a friendly 

 letter, to Mr. Herbert Spencer, who answered, in substance, that 

 he had not undertaken to deal with the ultimate cause, which he 

 had alleged to be unknowable. 



All the papers Mr. Croll had written on climatic subjects since 

 the publication of Climate and Time in 1875 were collected, re- 

 vised down to date, and republished at the end of 1885 under the 

 title of Discussions on Climate and Cosmology. " This completed 

 his work on geology and physics, and he quietly but deliberately 

 closed his reading and writing on those subjects, which had en- 

 grossed his attention for a period of twenty-five years, in which he 



