May 18, 1883.] 



SCIENCE. 



423 



that the record of an eminent scientific man, his 

 nature and his niuture, and his waj" of regarding 

 the important questions of his daj-, is material 

 which one -n'onld not willingly have lost. The 

 present memoir disclaims being written from a 

 scientific point of view ; and it does not, in fact, 

 furnish ground for modifying the very just esti- 

 mate of De Morgan which is given by Mr. 

 Jevons in the Encyclopaedia britannica. Nor 

 is it, on the other hand, a very personal me- 

 moir. The letters are nearly all addressed 

 to scientific friends, and are on questions of 

 general interest. His correspondence with his 

 wife and children, from whom he was seldom 

 separated, was fragmentar}', and not suited for 

 publication; and, with respect to domestic 

 details, his biographer has done what she 

 knew her hnsband himself would have wished. 

 He was always averse to making known what 

 nearly- concerned his family. 



De Morgan was born in the j'ear 1806, at 

 Madura, in the Madras presidencj-. His fa- 

 ther. Col. John De Morgan, was in the service 

 of the East India Company- ; and both his 

 grandfather and his great-grandfather had 

 served under Warren Hastings. His mathe- 

 matical powers, as well as his taste for music, 

 he derived from his mother, who was the grand- 

 daughter of James Dodsou, author of the anti- 

 logarithmic canon, a friend of De INIoivre, and 

 an early fellow of the Eoj'al society. Soon 

 after De Morgan's birth, the family returned 

 to England, and settled first at Worcester. The 

 3'oung Augustus was indoctrinated in various 

 branches of ' general knowledge ' in many 

 difl'erent private schools, after having learned 

 reading and numeration from his father at the 

 age of four years. His estimate of the character 

 of the instruction which he received appears, 

 from his belief in after }-ears,that, of exceptional 

 children, those who are least taught have the 

 best chance of a healthy development. One 

 element of his early teaching — the formal ob- 

 servances and the rigid religious doctrines in 

 which he was trained — strongij" tinged his 

 character in after life. He was made to learn 

 b}' heart long passages of Scripture, which, 

 from frequent repetition, had become meaning- 

 less to him ; he was talien to church twice in the 

 week and three times on Sundays, and required 

 to give an abstract of every sermon he heard, 

 until church became a place of penance to him, 

 and Snndaj' the one wretched daj- of the week. 

 In after j-ears he was unable to listen for anj- 

 length of time to speaking or preaching : to 

 get rid of memories of drearj' sermons, he had 

 to think of something different from what was 

 beiua; said. 



Until after tlie age of fourteen, he had shown 

 rather less than the usual aptitude for mathe- 

 matics. He said one day to an old gentleman, a 

 friend of the family, who saw him mailing with 

 great care a figure with ruler and compasses, 

 that he was ' drawing mathematics.' From him 

 the future mathematician learned, greatly to 

 his surprise, that he had hitherto missed the 

 aim of Euclid, and that geometry does not con- 

 sist in drawing accurate figures ; and he was 

 soon intent upon the first demonstration of 

 which he ever understood the meaning. From 

 that time his progress was rapid. At the age 

 of sixteen he entered Trinity college. Cam- 

 abridge ; and in his second year his tutor writes, 

 " He is not only in our first class, but far, very 

 far, the first in it." Airy, Peacock, and 

 Whewell were among the teachers whose in- 

 struction he particular!}- prized, and with whom 

 he kept up a life-long friendship and corre- 

 spondence. In 1827 he took the degree of 

 fourth wrangler only, his wide mathematical 

 reading having led him too often far away 

 from the courses prescribed for examination ; 

 and to the bitter disappointment of his mother, 

 who had hoped to see her oldest surviving son 

 in the church, he came up to London soon 

 afterwards, and entered at Lincoln's Inn. In 

 London he made the acquaintance of AVilliam 

 Frend, whom he describes as a man of singular 

 directness and clearness of mind, a clergyman 

 of the church of England, and a member of the 

 old Mathematical societj', who rejected negative 

 quantities and the doctrine of the Trinitj'. In 

 his house he became a frequent guest ; and his 

 children were surprised to find that this bril- 

 liant young man, of wliom great things were 

 expected in science, rivalled them in love of 

 fun and fair3'-tales and ghost-stories, and that 

 he could even show them a new figure in cat's- 

 cradle. It does not appear why so auspicious 

 a beginning did not result in his marriage to 

 Sophia Elizabeth Frend until ten j'ears later. 



The two great universities were closed to 

 De Morgan on account of his strong repugnance 

 to sectarian restraints on freedom of opinion ; 

 and hence he welcomed the opening of Univer- 

 sity college ( called at first the London uni- 

 versity ) , not only as meeting a great want of 

 the time, but as offering to himself a prospect 

 of leaving the study of law for a more congenial 

 occupation. Out of thirty-two candidates, he 

 was unanimously elected to the chair of mathe- 

 matics, in spite of his being only twenty-one 

 years of age. Tliree years later he handed in 

 his resignation. The professor of anatomy had 

 been removed on account of some complaints 

 preferred against him by his class ; and De 



