March 25, 1909] 



NATURE 



following suggestions, which are here reprinted with 

 a view to their being of use in a wider field : — 



Recomincndatioy\s regarding Mathemalical Notation and 

 Printing. 

 Always, 

 instead of 



^ a + d 

 3 2 



write 



a + - 

 2 



Til 



V- 



'-', 



ic + fd b + cfd 



instead of 



x.x + a slx-y 

 write 



x{x + a) sl(x-y)ox(x-y)'' 



In current ordinary text, 

 instead of 



X a + b 



a c + d 



write 



f t 



■*-/j'+; 



xja {a + d)/(c + d) x/iy + U) -t + JL 



y i + c 



Excessive use of the slanting line, or solidus, is, how- 

 ever, undesirable ; it may often be avoided by placing 

 several short fractions or formulas, with the intervening 

 words if any, on the same line, instead of setting out each 

 one on a line by itself. The last of the examples given 

 above illustrates an improper use, in which symmetry is 

 spoiled while nothing is gained ; either both fractions 

 should be written with the solidus, as x/y + al{b + c), or 

 else neither as above. 



The solidus should be of the same thickness as the hori- 

 zontal line which it replaces ; in some founts of type it is 

 too thick and prominent. 



Irregularities in the spacing of letters and symbols in 

 the formulas as printed are often the cause of a general 

 unsatisfactory appearance of the page. 



For centimetres, millimetres, kilometres, grams, kilo- 

 grams, the abbreviations should be cm., mm., km., gm., 

 kgm. (not cms., &c.), and so in similar cases. Present 

 custom is against the use of the signs .'. and '." 



Symbols which are not provided in the usual founts of 

 type are, as a rule, to be avoided. Compounded symbols 

 such as (j or d usually involve justification, and are thus 

 liable to become deranged or broken. The two examples 

 here given have, however, become so essential that separate 

 founts should be provided for them. 



The use of a smaller fount for numerical fractions is 

 now customary ; thus always ja instead of a/3. The use 

 ■of negative exponents often avoids a complex fractional 

 form ; as also the use of the fractional exponents, such as 

 2 and J. In the latter case x^ is usually preferred to a' -, 

 notwithstanding that the latter is more legible. 



Much is often gained in compactness and clearness by 

 setting out two or more short formulae on one line, instead 

 of on consecutive lines ; in that case they should be 

 separated by spaces, indicated by the sign ^ on the MS. 

 This would apply with even greater force to expressions 

 such as A; = a, =&, =c. 



In the preface to his " Mathematical and Physical 

 Papers," vol. i., 1880, the late Sir George Stokes success- 

 fully introduced the limited use of the solidus notation, 

 obtaining the assent and support of Lord Kelvin, Prof. 

 Clerk Maxwell, Lord Rayleigh, the editors of the Annalen 

 der Physik, and many other mathematicians. He defined 

 its use as restricted to the symbols immediately on the 

 two sides of it, unless a brace or stop intervenes ; thus 

 I slnnirx/a is to mean sin(nir.x'a); but sin ne./r", in case 

 I it is used, would mean (s\n n9)lr". 



NO. 2056, VOL. 80] 



NOTES. 



Prof. Cleveland Abbe, of the U.S. Weather Bureau, 

 Washington, Dr. J. R. Sutton, of Kimberley, South Africa, 

 and M. L^on Teisserenc de Bort, of Paris, have been elected 

 honorary members of the Royal Meteorological Society. 



.'\t the meeting of the Royal Geographical Society on 

 April 5, Sir Harry Johnston, who has just returned from 

 his journeys through the southern States and the West 

 Indies, will give a lecture on the scenery of Cuba, Haiti, 

 and Jamaica, with many illustrations from photographs 

 taken by himself. 



The death' is announced, at the age of sixty-four years, 

 of Prof. J. W. Moore, professor of phj-sics in Lafayette 

 College at Easton, Pennsylvania, since 1872. 



Sir Rowland Blennerhassett, whose death at sixty- 

 nine years of age we announce with great regret, was not 

 only distinguished in his political career and historical 

 studies, but also by his influence upon education in Ireland. 

 For about seven years he was H.M.'s Inspector of Indus- 

 trial and Reformatory Schools in Ireland. From 1897 to 



1904 he w^as president of Queen's College, Cork, and in 



1905 he was appointed a visitor of the college. He was 

 a senator of the Royal University of Ireland in 1897, and 

 was a member of the standing committee of the Senate. 

 He was also one of the Commissioners of National Educa- 

 tion in Ireland, and took an active part in the administra- 

 tion of that department down to the time of his death. 



It should have been mentioned last week in the article 

 on the Imperial Bureau of Ethnology (p. 73) that the 

 Sirdar, Sir Reginald Wingate, is so impressed with the 

 necessity of a thorough study of native conditions as the 

 basis of good government that he has provided a grant 

 for an investigation of the ethnology of the Sudan, especi- 

 ally from the sociological side. This work, which will 

 extend over at least two winters, has been entrusted to 

 Dr. C. G. and Mrs. Seligmann, who have recently made 

 a joint investigation on the Veddas. Some of our colonial 

 Governments also appreciate the value of such studies. 

 For example, the" expedition of the Seligmanns was financed 

 by the Ceylon Government, and Mr. N. W. Thomas has 

 been appointed Government ethnologist to Southern 

 Nigeria, and is at the present time engaged in collecting 

 information concerning the sociology and religion of that 

 district. 



The honorary secretaries of the Zoological Society of 

 Scotland (42 Frederick Street, Edinburgh), which has 

 recently been founded, inform us that the society has been 

 formed for the purpose of establishing a living zoological 

 collection and garden at Edinburgh. The garden will be 

 arranged on the system adopted by Herr Hagenbeck, of 

 Hamburg, and wiU be conducted on scientific lines. When 

 the society has developed sufficiently, it is within its scope 

 to establish branch gardens in the other large towns in 

 Scotland. In addition to this — its main object — lectures 

 of a popular nature by eminent zoologists will be arranged. 

 The headquarters of the society, and the first and principal 

 garden, will be at Edinburgh. To obtain the necessary 

 'capital a garden fund has been opened, to which donations 

 are solicited. The annual subscription is il. js., but 

 members who join the society during 1909 pay los. only 

 for that year. This will entitle members to all the 

 privileges usual in such a society. The aim of the pro- 

 moters is to build up a strong society with a large member- 

 ship, so that a considerable part of the annual sum re- 

 quired for the upkeep of the gardens will be ensured from 

 subscriptions, and less dependence will require to be placed 

 on the receipts from the public for admission. 



