September 4, 1919] 



NATURE 



1 1 



though fortunately in this case the specimens from 

 which the plates were drawn are preserved in the 

 Sloane Herbarium in the British Museum. Linnaeus 

 (1753) defined four species, the two Old World forms 

 and two -American, one of the latter being G. bar- 

 badense, presumably the parent of the " Sea Island " 

 cotton. 



Meteorological Office Circulars Nos. 37 and 38, 

 isjued July i and August i respectively, deal with 

 current official notices. Reference is made in 

 the Julv circular to Professional Notes No. 7 — "The 

 Climate of North-West Russia," which was prepared 

 for the use of the British forces acting on the Mur- 

 man coast. The general climate is discussed for the 

 district extending from the Arctic Ocean on the north 

 to Petrograd and the Gulf of Finland on the south, 

 and from the Swedish frontier on the west to 45° east 

 on the east. It deals with the dates of the thawing 

 and freezing of the rivers. The temperature of the 

 u|'l)er air is discussed, and other meteorological 

 information is given. Upper-air temperatures in 

 the north-east of France are given for the end ot 

 April last as being of interest in connection with 

 the heavy snowfall over England on April 27. The 

 upper air was abnormally cold. The August circular 

 has an obituary notice of Lord Rayleigh. 



The very effective hardening solution for gelatine 

 negatives that Messrs. Ilford, Ltd., recently intro- 

 duced is applied as a preliminary bath, before develop- 

 ment, and enables development, etc., to be carried on 

 at as high a temperature as 110° F. without any 

 cooling being necessary. In the specification of the 

 patent granted to Messrs. Agnew and Renwick, both 

 of Messrs. Ilford, Ltd. (see British Journal of 

 Photography, August 8), it is stated that the formal- 

 dehyde, which is the real hardening agent, is mixed 

 with a salt of the class which tends to restrict the 

 swelling of dry gelatine in water and raise its melting- 

 point, so that even though the bath m.ay be at as high 

 a temperature as 110° F.. the gelatine has no oppor- 

 tunity of melting before it is hardened by the forma- 

 line. This class of salts includes acetates, tartrates, 

 citrates, oxalates, sulphates, phosphates, chromates, 

 bicarbonates, and borates. Example formula are 

 given, using sodium sulphate and ordinary sodium 

 phosphate. 



X PAMPHLET issued by the Optical Pyrometer Syndi- 

 cate, of Audrey House, Ely Place, E.C.i, contains 

 some notes on optical pyrometers in general, and_ a 

 special account of the "wedge" pyrometer and its 

 uses. The early form of this instrument was described 

 in Nature for Julv 22, 1915, the principle relied upon 

 bring the complete extinction of the source of light 

 bv means of a wedge of dark glass interposed between 

 the eye and the source, the temperature being deduced 

 from the thickness of dark glass needed to secure 

 extinction. It is claimed that not only can concordant 

 results be obtained by a single observer trained to the use 

 of the instrument, but also that separate observers may 

 obtain readings agreeing to within 20° C. at 1500° C. 

 One of the disadvantages of all optical pyrometers is 

 that the personal judgment of the operator must be 

 relied upon, either :n matching tints or in producing 

 total extinction, and for these purposes all eyes are 

 not equally sensitive. In view of the great increase 

 in the use of optical pyrometers, an impartial investiga- 

 tion of the various types from this point of view 

 would be an advantage, due regard being paid to 

 the tvpe of observer employed in workshops. If the 

 agreement in readings claimed for the " wedge " pyro- 

 meter should prove to be general for all types of 

 observer, this instrument ought to be very useful, and 



NO. 2601, VOL. 104] 



its simple construction a recommendation for indus- 

 trial purposes. 



According to an editorial note in the Scientific 

 American for July ig, the romance of invention is to 

 be illustrated in a series of articles on Americans who 

 have produced inventions of the first rank which have 

 proved financially successful. The whole record shows 

 that the ability to invent and the ability to make a 

 commercial success of an invention are seldom com- 

 bined in one man, and the editor almost regards them 

 as mutually exclusive. The first article of the series 

 deals with the telephone. Dr. Graham Bell, who is 

 noiv seventy-two, invented the telephone in 1876. He 

 himself says he is not a business man and that his 

 interest in the commercial side of an invention is 

 small. He was, however, in the early days of the 

 telephone so fortunate as to be associated with able 

 business men who not only made it a commercial 

 success, but also safeguarded the inventor's interests 

 in such a way that its success was of benefit to him. 

 It is not desirable that so large a proportion of those 

 who invent or discover something of the greatest value 

 to humanity should see the reward pass to others 

 while they themselves get little or no recognition from 

 their country or the world at large. 



The Journal of the British Science Guild for July 

 contains a summary of the proceedings of various 

 committees, including those dealing with education 

 and with the metric system, and an account of the 

 thirteenth annual meeting held on June 17. The 

 education committee emphasises the unfavourable 

 position of this country, as regards both the financial 

 position of institutions for higher education and 

 the number of students of university grade, in 

 comparison with other countries. A detailed report 

 on " Industrial Research and the Supply of Trained 

 Scientific Workers " has been sent to the Prime 

 Minister, to the President of the Board of Education, 

 and to universities and similar educational bodies. 

 Special attention has also been devoted by the guild 

 to the organisation of research in relation to fisheries, 

 and importance is attached to the establishment of 

 an institute and museum of oceanography,- similar to 

 those in existence in Berlin and in contemplation in 

 Denmark. The attention of the Government has also 

 been directed to the importance of establishing a 

 strong optical industry in this country. A measure 

 recommended is the introduction of certificates of 

 origin of optical goods as a safeguard against fraudu- 

 lent competition. The report of the thirteenth annual 

 meeting includes the addresses delivered on that occa- 

 sion by Major-Gen. Seely, Lord Sydenham, and Sir 

 J. J. Thomson. The journal also contains an apprecia. 

 tion of the late Sir Boverton Redwood by Prof. F. 

 Clowes. 



Mr. Edward Arnold announces a new series entitled 

 The Modern Educator's Library. The general editor 

 is Prof. A. A. Cock, and the aim is to present the 

 considered views of teachers of wide exoerience and 

 ability upon the changes in method involved in the 

 development in educational theory and practice, and 

 upon the problems as yet unsolved. The first volume 

 of the series (by Prof. T. Percy Nunn) will form an 

 introduction to 'it, and will deal' with the fundamental 

 questions which lie at the root of educational inquiry. 

 It will be entitled "Education: Its Data and First 

 Principles." Succeeding volumes will be "Moral and 

 Religious Education," Dr. Sophie Bryant; "The 

 Teaching of Modern Foreign Languages in School 

 and University," Prof. H. G. Atkins and H. L. 

 Hutlon; and "The Child under Eight." E. R. 

 Murrav and H. Brown Smith. Other books_ an- 

 nounced bv the same publisher are : — " A Physician 



