March 20, 1919] 



NATURE 



49 



Air Board research departmenl on having- over- 

 come all the difficulties. 



The promise for the future of aviation is vcrv 

 bright, and the recc^nition of the necessitv for 

 continuous research in the development of 'both 

 military and civilian aeronautics leaves little 

 doubt that the resources of scientific investigation, 

 which have been of incalculable value during the 

 war, will be fully employed in the solution of the 

 oroblems of the future. 



LUDVIG SYLOW. 

 "T^HE death of Ludvig- Sylow (September 7, 

 J- 1918), at the age of eighty-five, has removed 

 an eminent mathematician, whose career was in 

 many ways remarkable. Sylow 's seventh pub- 

 lished paper ("Theorfemes sur les groupes de sub- 

 stitutions ") occupies less than ten pages in vol. v. 

 of the Mathematische Annalen (1872); this con- 

 tains the proof of his justly celebrated theorem 

 about groups, which has perhaps done more than 

 any other single proposition to advance our know- 

 ledge of groups in general. In spite of this great 

 achievement, Sylow had to earn his living as a 

 secondary-school teacher until he had served a 

 term of forty years. Recognition came at last ; he 

 was made professor at Christiania at the age of 

 sixty-five, and filled the chair successfully for 

 twenty years. 



It may be of interest to recall Sylow's own 

 statement of his theorem : " Si w^ d^signe la plus 

 grande puissance du nombre premier n qui divise 

 I'ordre du groupe G, ce groupe contient un autre 

 g de I'ordre ?i"; si de plus n"v d^signe I'ordre du 

 plus grand groupe contenu dans G dont les sub- 

 stitutions sont permutables k g, I'ordre de G sera 

 de la forme n"v(n/)+i)." It should be noted that 

 Sylow gives a proof that, if rr is the highest 

 power of n contained in the order of G, then G 

 contains a subgroup of order n". 



Sylow wrote a number of other papers, dealing 

 with such topics as group-theory, solution of equa- 

 tions by radicals, elliptic functions, modular func- 

 tions, etc. In collaboration with Lie he undertook 

 the arduous task of editing the second issue of 

 Abel's works. In this the misprints and over- 

 sights of the original edition are corrected, and 

 a number of valuable notes and comments by the 

 editors are added. G. B. M. 



NOTES. 



The appointment of Dr. S. F. Harmer to succeed 

 Sir Lazarus Fletcher as director of the Natural His- 

 tory Museum, South Kensington, is a happy solution 

 of the question raised by the letter from twenty-three 

 naturalists published in Nature of March 6, and com- 

 mented upon by us in the same issue. Dr. Harmer 

 has been keeper of the Department of Zoology of the 

 museum since 1907, and he will retain this position 

 until the end of next year. During this transition 

 period Mr. C. E. Fagan, the assistant secretary, will 

 assist him in the control of the museum, and, in 

 recognition of his valuable services, will occupy a 



NO. 2577, VOL. 103] 



I considerably impro\.-d position on the staff, Mr. 

 I C. late Regan has been aj^inted assistant keeper 

 I of zoology in succession 10 Mr. VV. R. Ogilvie Grant, 

 who has retired. As ihe Trustees have appointed a 

 distinguished naturalist to the directorship of the 

 museum, the series of eminent scientific men who have 

 occupied that post remains unbroken. It is the duty 

 of men of science to guanl jc.lously their claims to 

 direct the affairs of scientific institutions, and to pro- 

 test when any encroachment upon them is contem- 

 plated. In the present instance Mr. Fagan was more 

 than a purely lay administrator, and his scientific ser- 

 vices have been appropriately recognised by the 

 Trustees. The tendency is, however, to place lay ad- 

 ministrative officers in control of State institutions 

 concerned with scientific work, on the ground that a 

 man of science cannot be a good administrator. 

 Even if this general belief, cherished in the Civil 

 Service, could be justified — and we do not accept it 

 for a moment — the highest office in a scientific in- 

 stitution should be held by a scientific man, and not 

 by a lay official. That Is the whole point of our 

 contention, and we are glad that the Trustees have 

 accepted what is the feeling of scientific men 

 generally in regard to it by appointing Dr. Harmer 

 to the vacant post, which he is highly qualified to 

 fill. • 



Lord Sudeley is to be thanked for having brought 

 the House of Lords to such a high appreciation of 

 museums as educational instruments that, on March 12, 

 in the face of some Government objections, it whole- 

 heartedly agreed to his motion : — "That his Majestv's 

 Government should, without further delay, reinstate 

 the system of providing official guide-lecturers for the 

 museums and picture galleries under the control of 

 the Government, which, with one exception, has been 

 in abeyance during the war, making such addition to 

 the numbers and in the salaries and status of the 

 guides as may be found necessary." The Government, 

 it seems, is prepared to reinstate the pre-war conditions, 

 but is not prepared to increase the numbers or salaries 

 of the guide-lecturers ; neither does it act with prompt, 

 ness in clearing the museums of alien departments. 

 There can be no doubt as to the popular feeling in this 

 matter, and when, twice within a fortnight, it is 

 supported in the Upper Chamber by men of such 

 weight as Lords Crewe, Harcourt, Meath, Morris, 

 Gainford, and Rathcreedan, then a Government which 

 contains many sympathetic elements should surelv 

 be emboldened to spend the relatively minute sum 

 needed to set all this valuable educational machinery 

 in motion. His Grace the Archbishop of Canterbury 

 urged that an increased number of guides would 

 permit the extension of co-operation between the 

 British Museum and the primary schools through lee- 

 tures to the teachers, who would then take their 

 classes to the museum ; there could also then be an 

 extension of similar aid to schools of art and secondary 

 schools. Incidentally, the Primate took occasion to 

 extol the merits of the British Museum guide-books, 

 from which, he rightly said, visitors might derive 

 muc'h advantage. Can he be aware that the General 

 Guide to the Natural History Museum has been out 

 of print for some years, and that a sale of many 

 thousands to the visiting troops and others has thus 

 been lost? A new edition of this guide should be 

 an early claim on the time of the new director. 



The question of long-distance wireless telegraph 

 communication is now engaging the attention of a 

 Committee recently appointed by the War Cabinet, 

 with Lord Milner as chairman. The need for action 



