400 



NATURE 



[February 25, 



Hirst received a cordial welcome from the mathematicians 

 of Southern Italy, and then going north he followed the 

 victorious armies as far as San Martino and Solferino. 

 After the Peace of Villafranca he visited the town of 

 Cremona, and here commenced an acquaintance of life- 

 long duration with Prof. Luigi Cremona. 



In i860, Dr. Hirst took up his residence in London, 

 and for a short time took the advanced mathematical 

 classes in University College School, in consequence of 

 Mr. Cook's illness, and on that gentleman's death he 

 became his successor. This office Dr. Hirst held for five 

 years, and here, with Prof Key's full concurrence (see 

 Dr. Hirst's preface to Wright's " Elements of Plane 

 Geometry," 1868), he taught geometry to classes of be- 

 ginners without the use of " Euclid." Subsequently, in 

 1870, at the request of the Ladies' Educational Associa- 

 tion, he gave a course of twenty-four lectures on the 

 subject of geometry to a class of sixty ladies at St. 

 George's Hall. The syllabus of these lectures was 

 printed at the time. He was so well satisfied with the 

 results of his attempt that when, in 1871, the Associa- 

 tion for the Improvement of Geometrical Teaching was 

 started, though he had taken no part, directly, in its 

 formation,^ he at once gave in his adhesion to the move- 

 ment, and contributed very materially to its success, by 

 his accepting the office of President, and by his doing 

 yeoman's service during his tenure of the office (1871-78). 

 Previous to this Dr. Hirst had, in 1865, been elected 

 Professor of Mathematical Physics in University College. 

 This post he vacated in 1867, when he succeeded Prof 

 de Morgan in the Chair of Pure Mathematics. It was on 

 January 16, 1865," that the London Mathematical Society 

 was started. Of this Society Dr. Hirst was one of the 

 pillars, and it was in a great measure through his foster- 

 ing care that it has made the mark it has. He served on 

 the Council from 1865 to November 1885, and for the 

 session 1890-91. He vacated the office of Treasurer 

 when he was elected President for the years 1872-73, 

 1873-74. 



In 1870, Dr. Hirst was appointed to the new office of 

 Assistant Registrar to the University of London, and 

 thereupon resigned his Professorship, and the General 

 Secretaryship of the British Association, which he had 

 held from 1866. In 1873, when the Royal Naval Col- 

 lege was founded, he became the Director of Studies, and 

 held the office for ten years, when the precarious state of 

 his health necessitated his retirement, and the passing of 

 several winters abroad. He died on February 16. 



In 1861, Dr. Hirst was elected a Fellow of the Royal 

 Society. He was three times a member of the Council 

 of the Society, and twice one of its Vice-Presidents. In 

 1883 one of the Royal Medals was awarded to him for 

 "his investigations in pure geometry ; and, more particu- 

 larly for his researches into the correlation of two planes 

 and into the complexes generated by them." He was a 

 Fellow of the Royal Astronomical Society, a member of 

 the Physical Society, and of several Continental Societies. 

 He served for some years on the Council of University 

 College, London, and was also a member of the Senate 

 of the University of London. 



Dr. Hirst revised the mathematical articles in Brande's 

 " Dictionary of Arts and Sciences," and contributed new 

 ones ; and published a translation of Clausius's treatise on 

 " The Mechanical Theory of Heat " (1867), 



The following titles of papers mav be mentioned : — 

 " On the Volumes of Pedal Surfaces "'(Phil. Trans., 1863 ; 

 Crelle, Ixii., 1863 ; and Tortolini, Annali, v., 1863). " On 

 the Quadric Inversion of Plane Curves" (R.S. Proc, 

 1865 ; cf Chasles, " Raj)port," p. 167, " Cememoire estun 

 travail fort complet''). This was his first ;>«r^/)' geo- 

 metrical paper. It was translated by Cremona in the 



I Opening remarks in the Presidential Address, A.I.G.T., First Report, 

 January 17, 1871 (cf. also Nature, vol. ii. pp. 65, 141, 164). 

 ^ Memoir of Augustus de Morgan, pp. 280-S6. 



Annali di Matemattca (vii., 1865), and a form of it is 

 published in the Nouvelies Annates (v., 1866;. His re- 

 maining papers, mainly contributed to the London 

 Mathematical Society's Proceedings, are :— " On Correla- 

 tion in Space" (abstract of Presidential Address, 1874, 

 Proc, vi.). "Note on the Correlation of Two Planes" 

 (Proc, viii.). " On Cremonian Congruences" (Proc, xiv.). 

 "On Congruences of the Third Order and Class" 

 (Proc, xvi.). " On Cremonian Congruences contained in 

 Linear Complexes" (Proc, xvii.). "On the Correlation 

 of Two Spaces, each of Three Dimensions" (Proc, xxi.). 

 " On the Complexes generated by Two Correlative 

 Planes" {Chelini Memorial Volume, 1881). " Sur la 

 Congruence Roccella " {Circolo Matematico, 1886). 



DR. THOMAS S TERRY HUNT. 



T^R. T. STERRY HUNT, who died at New York on 

 -*-^ the 1 2th of this month, in his sixty-sixth year, was 

 widely known from his geological works, especially those 

 relating to chemical geology. For some years past he 

 had been in feeble health, suffering much from heart- 

 disease. Early in this year he was attacked with influ- 

 enza, from which he seemed to be recovering, but a 

 relapse occurred, from which he failed to rally. Born on 

 September 6, 1826, at Norwich, in Connecticut, he was 

 educated for the medical profession, but in 1845 became 

 assistant to Prof. B. Silliman at Yale College, and was 

 also chemist to the Geological Survey of Vermont. In 

 1847 he joined the Geological Survey of Canada, under 

 Sir W. Logan, as chemist and mineralogist. From 1856 

 to 1862 he was Professor of Chemistry at Laval Uni- 

 versity in Quebec, giving his lectures in French. From 

 1872 to 1878 he was Professor of Geology at the Massa- 

 chusetts Institute of Technology. He was elected a 

 Fellow of the Royal Society in 1859, and in 1881 received 

 the honorary degree of LL.D. at Cambridge. Dr. Hunt 

 was one of the founders of the International Geological 

 Congress at Philadelphia, in 1876 ; he attended the 

 meetings of the Congress at Paris in 1878, Bologna in 

 1881, Berlin in 1885, and London in 1888, taking an 

 active part in the proceedings of each. 



Although by birth a citizen of the United States, he is 

 best known as a Canadian geologist, and, after retiring 

 from the Canadian Survey, he lived for some years in 

 Montreal. But latterly he preferred to consider himself 

 once more as belonging to the United States, and for a 

 few years before his death was a resident in New York. 



Dr. Hunt's most important geological work was done 

 in connection with the Geological Survey of Canada, 

 with and under Logan. They led the way in the study of 

 the Archaean rocks of that area, and Hunt gave to them 

 many of the names which have since become well known, 

 and too widely used, in .the Archaean controversy. His 

 work on the geology of petroleum was of high value, and 

 he long ago clearly stated generalizations as to its occur- 

 rence which later investigations, over wider areas in 

 North America and in other districts, have fully verified. 

 Other important researches, published in the official 

 Reports of the Canadian Survey and elsewhere, related 

 to limestone, dolomite, and gypsum ; salt ; the chemistry 

 of natural waters ; the porosities of rocks ; rock-weather- 

 ing, &c. The well-known "Geology of Canada," issued by 

 Logan in 1863 as Director of the Survey, was in large 

 part written by Hunt, the parts on lithology and on 

 economic geology being almost entirely his ; he likewise 

 read the proofs of the whole. He also wrote much on 

 Alpine and Italian geology, and on the classification of 

 the older Palaeozoic rocks ; in the Cambro-.Silurian con- 

 troversy he was a warm advocate of Sedgwick. The 

 origin of serpentine was also a favourite subject, he 

 stoutly maintaining its aqueous origin. As regards the 

 ancient crystalline rocks generally, he to a large extent 



NO. 1165, VOL. 45] 



