September 15. 1904] 



NA TURE 



Balata, Mimusops globosa, and of the imported timber 

 trees, Honduras mahogany and African mahogany, Kasya 

 scncgalensis, are growing freely 



For the forthcoming new edition of the " Imperial 

 Gazetteer of India," Sir J. D. Hoolier has written a chapter 

 on the flora of India, which is prefaced by an introductory 

 summary. With the authority of the Secretary of State 

 for India, this chapter has been issued in an advanced form, 

 and the summary is reprinted in the Journal of Botany 

 (August). In the same number an account will be found 

 of certain changes which will be proposed at the forth- 

 coming congress of botanists to be held at Vienna in June, 

 1905, in connection with the rules which govern botanical 

 nomenclature. The three lists of suggestions here given 

 take the form of alterations in, or additions to, the Paris 

 code, and have been drafted respectively by British botanists 

 of the British Museum, .\merican botanists of the Gray 

 Herbarium, and a group of Italian botanists. 



The latest addition to the .Manueli Hoepli is a handbook 

 dealing with artisan dwellings, by the engineer Effren 

 Magrini, of Turin. In the same series Dr. Guido 

 Sandrinelli has issued a new and completely revised edition 

 of the manual of the late Pietro Gallizia on strength of 

 materials and applied elasticity. It deals with calculations 

 of strains and stresses in beams and other structures, and 

 allied problems of use to the practical engineer. 



No. 5 of the Bulletin of the Belgium .\cademy of Sciences 

 contains an account by A. de Hemptinne of a remarkable 

 electrolytic synthesis of stearic acid from oleic acid. This 

 acid, when subjected in an atmosphere of hydrogen to the 

 discharge of a Tesla transformer, combines with the gas 

 to form principally stearic acid. In No. 6 of the Bulletin 

 is a description of the preparation and properties of a 

 number of fluorine-substituted amines. These substances 

 are remarkable because of their extraordinary stability as 

 lompared with the corresponding chloro- and bromo- 

 derivatives, which, as a rule, decompose rapidly at the 

 ordinary temperature. 



To the Smithsonian Miscellaneous Collections (vol. xlv., 

 parts iii. and iv.) Prof. F. A. Lucas contributes an account 

 of a nearly perfect skeleton of a pavement-toothed iguanodon 

 ( Trachodon or Claosaurus). The edentulous predentary and 

 premandibular bones of the iguanodont dinosaurs are con- 

 sidered by the author to have been sheathed in horn, and 

 thus to have formed a beak adapted for nipping off the 

 branches or herbage on which these reptiles fed. Among 

 other contributors to the same part are also Messrs. Jordan 

 and Snyder, who describe several new deep-water fishes from 

 Japan. These include a shark of the genus Pristiurus, as 

 well as one of Pseudotriacis, and likewise a new genus, 

 Trismegistus, allied to Liparis. Trismeglslus owstoni, as 

 the third of these new species is called, is certainly a very 

 remarkable fish, somewhat like a sole in shape, although, 

 of course, bilaterally symmetrical, with the skin dotted with 

 prickles supported on broad bases, so as to recall inverted 

 drawing-pins. 



Is the August number of the American Journal of Science 

 .Mr. Bertram B. Boltwood records observations which 

 indicate that the quantities of radium present in several 

 uranium minerals, which have been examined, are directly 

 proportional to the quantities of uranium contained in the 

 minerals. This is perhaps to be regarded as experimental 

 evidence in favour of the suggestion that radium is formed 

 by the breaking down of the uranium atom. 



NO. 1820, VOL. 70] 



In the August issue of the Annales de Chimie et de 

 Physique is a contribution by Messrs. Moissan and Rigaut 

 on the use of metallic calcium in the preparation of argon. 

 It is shown that the last traces of nitrogen, which are not so 

 easily removed by a heated mixture of lime and- metallic 

 magnesium, are readily absorbed by passage of the gas over 

 a small quantity of metallic calcium. An apparatus is 

 described in which argon can be continuously produced at 

 the rate of a litre every twelve hours. 



Some interesting experiments relating to the electrolytic 

 reduction of carbonic acid are described by Messrs. Coehn 

 and Jahn in the Berichte der deutschen chemischen Gesell- 

 schaft (vol. xxxvii. p. 2836). The reduction cannot be 

 effected in acid solutions or in solutions containing the 

 normal carbonates, but takes place readily in bicarbonate 

 solutions. From this the authors conclude that the re- 

 ducing action is limited to the bicarbonate ion, and that the 

 carbonate ion and the undissociated carbonic acid molecule 

 are not reducible. The reduction only takes place at those 

 electrodes at which hydrogen is discharged at a considerable 

 over-voltage, and the product of reduction is formic acid. 



We have received a copy of the report and recommend- 

 ations presented to the Pharmacopoeia Committee of the 

 General Medical Council by Prof. Wyndham R. Dunstan 

 and Mr. H. H. Robinson with reference to the tests for 

 the detection of arsenic in the drugs of the British 

 Pharmacopoeia. It is found that the test proposed by 

 Mayen^on and Bergeret in 1874, if performed under certain 

 conditions, is best adapted to the purpose. This test 

 depends on the production by arseniuretted hydrogen of a 

 stain on paper soaked in mercuric chloride. The method 

 possesses the advantage of requiring only such a degree of 

 purity in the acid and zinc as is to be found in purchaseable 

 materials, and thus avoids the special purifications involved 

 in the Marsh-Berzelius test. The stain decided on as the 

 standard of comparison is that given by 0012 milligram of 

 arsenic. 



OUR ASTRONOMICAL COLUMN. 



Re-discovery of Encke's Comet. — .\ telegram from the 

 Kiel Centralstelle announces the re-discovery of Encke's 

 comet at the Koenigstuhl on September 11. The position 

 of the comet at I3h. lepm. (local M.T.) was 



R..A. = ih. 46m. i6s., dec. = -(-25° 24'. 



These positions seem to be very slightly lower than the 

 apparent positions given in the ephemeris reproduced in 

 these columns on September 8. As this is the second comet 

 of this year, it will be designated 1904 h. 



Dr. Common's 6o-inch Reflector. — In Circular No. S3 

 of the Harvard College Observatory, Prof. E. C. Pickering 

 announces that, thanks to the generosity of. an anonymous 

 donor, who, unconditionally, gave twenty thousand dollars 

 to the observatory, and to the intermediary services of Prof. 

 Turner, the observatory has been able to purchase the well 

 known 60-inch mirror which was made by the late Dr. 

 Common. 



.Arrangements are being made to transport the mirror to 

 Cambridge (Mass.) as soon as possible, and, when mounted, 

 it will be used to complete the photometric survey of the 

 heavens which has been so thoroughly — so far as means 

 would permit — prosecuted at Harvard. With an instru- 

 ment of this aperture it will be possible to measure the light 

 of the very faintest stars known. 



Prof. Pickering states that Mr. T. A. Common, from 

 whom the mirror was purchased, let them have it on such 

 favourable terms that he may fairly be regarded as having 

 contributed a large portion of the cost. 



