376 THE POPULAR SCIENCE MONTHLY. 



very strong, and bring out its less obvious parts into startling promi- 

 nence. Much especially is to be learned of character by taking into 

 consideration the employment of times of leisure or relaxation, the 

 occupation of such hours being due almost solely to the natural bent 

 of the individual, without the interfering action of necessity or ex- 

 pediency. Most men, perhaps especially eminent men, have a "hob- 

 by," some absorbing object, the pursuit of which forms the most 

 natural avocation of their mind, and to which they turn with the cer- 

 tainty of at least satisfaction, if not of exquisite pleasure. The man 

 who follows any branch of natural science in this way is almost always 

 especially happy in its prosecution, and his mental powers are re- 

 freshed and invigorated for the more serious and engrossing, if less 

 congenial, occupation of his life. Mr. Mill's hobby was practical field 

 botany ; surely in all ways one very well suited to him. 



Of the tens of thousands who are acquainted with the philosophi- 

 cal writings of Mr. Mill, there are probably few beyond the circle of 

 his personal friends who are aware that he was also an author in a 

 modest way on botanical subjects, and a keen searcher after wild 

 plants. His short communications on botany were chiefly, if not en- 

 tirely, published in a monthly magazine called the Phytologist, edited 

 from its commencement in 1841 by the late George Luxford till his 

 death in 1854, and afterward conducted by Mr. A. Irvine, of Chelsea, 

 an intimate friend of Mr. Mill's, till its discontinuance in 1863. In the 

 early numbers of this periodical especially will be found frequent 

 notes and short papers on the facts of plant-distribution brought to 

 light by Mr. Mill during his botanical rambles. His excursions were 

 chiefly in the county of Surrey, and especially in the neighborhood of 

 Guildford and the beautiful vale of the Sittingbourne, where he had 

 the satisfaction of being the first to notice several plants of interest, as 

 Polygonum dumetorum, Isatis tinctoria, and Impatiens fulva, an 

 American species of balsam, affording a very remarkable example of 

 complete naturalization in the Wey and other streams connected with 

 the lower course of the Thames. Mr. Mill says he first observed this 

 interloper in 1822, at Albury, a date which probably marks about the 

 commencement of his botanical investigations, if not that of the first 

 notice of the plant in this country. Mr. Mill's copious MS. lists of ob- 

 servations in Surrey were subsequently forwarded to the late Mr. Sal- 

 mon of Godalming, and have been since published with the large col- 

 lection of facts made by that botanist in the " Flora of Surrey," printed 

 under the auspices of the Holmesdale (Reigate) Natural History Club. 

 Mr. Mill also contributed to the same scientific magazine some short 

 notes on Hampshire botany, and is believed to have helped in the 

 compilation of Mr. G. G. Mill's " Catalogue of the Plants of Great 

 Marlow, Bucks." 



During his frequent and latterly prolonged residence at Avignon, 

 Mr. Mill, carrying on his botanical observations, had become very well 



