2 3 8 



NA TURE 



[January 8. 1903 



study, manual training and household science, and for advanced 

 pupils to obtain instruction in agriculture, horticulture and allied 

 subjects. It stimulates public interest in the schools and brings to 

 the pupils of a township an institution in which all can have an 

 equal interest and a worthy pride. 



The address given by Sir J. Wolfe Barry on Tuesday, as 

 president of the Association of Technical Institutions, contained 

 several instructive comparisons as to the position of technical 

 education at home and abroad. For instance, he pointed out 

 that while the matriculated students in German technical high 

 schools number 15,442, fhe number in the whole of similar 

 institutions and universities of Great Britain is only 3S73. But 

 it is not so much the number of students as the spirit in which 

 scientific knowledge is regarded that is of importance to national 

 progress. What is wanted. Sir J. Wolfe Barry remarked, is. first, 

 that the highest intellects among us for research as applied to the 

 arts should be rendered available, and secondly, the best pos- 

 sible directing minds should be discovered and utilised in our 

 manufactures. In other words, the man of science should be 

 encouraged to help in the development of industries. Efforts 

 should be made to ensure that industrial leaders are well 

 equipped with scientific knowledge and the principles of tech- 

 nology, and in our schools less time should be given to dead 

 languages and more to the efficient study of science, applied 

 mathematics and other subjects demanded by modern life. 

 Finally, everyone should endeavour, each in his own sphere of 

 influence, to direct, without any exaggeration, but with pro- 

 found conviction, the attention of our commeicial classes to the 

 fact that technical education of the best and most thorough kind 

 is an urgent and crying necessity if we are to maintain a lead- 

 ing position among the nations of the world. 



SOCIETIES AND ACADEMIES. 



London. 



Royal Society, December 11, 1902. — "An Error in the 



Estimation of the Specific Gravity of the Blood by Hammer- 

 schlag's Method, when employed in connection with Hydro- 

 meters." By A. G. Levy, M.D. (London). Communicated 

 by Sir Victor Horsley, F.R.S. 



Hammerschlag's method may be briefly described as the 

 adjustment of the specific gravity of a mixture of chloroform and 

 benzol by small successive additions of either constituent until it 

 corresponds to the specific gravity of the blood, the test of the 

 attainment of this condition being that a small drop of the blood, 

 when immersed in the mixture, shall remain suspended without 

 any very obvious tendency to rise or sink. The specific gravity 

 of the mixture is then estimated by means of a hydrometer. 



This method is known to be liable to an error of varying 

 magnitude. The investigation into the source of this error 

 resolved itself into a series of observations upon the effect of the 

 low value of the surface tension of the above mixiure upon the 

 readings of hydrometers immersed therein. The surface tension 

 of the mixture may be taken as 2 75 mg. per mm., and that of 

 clean tap water as 7*3 mg. 



The readings of four different hydrometers when immersed 

 in a mixture of the specific gravity I'OOO are appended : — 



No. of hydrometer. No. 1. No. 2. No. 3. No. 4. 



Reading of scale in a"! 

 chloroform benzol I 



mixture of specific f I '° 02 l °°3 IO °95 i"oio 

 gravity = 1 'ooo J 



The author found, however, that the calculated errors exceeded 

 in each instance those observed, and the results are contrasted in 

 the following table : — 



The difference was accounted for satisfactorily by an innate 

 error demonstrated to exist in each hydrometer, evidently due 

 to the standardisation of the instrument in unclean (i.e. greasy) 

 water, which possesses a lower surface tension than 7-3 mg. 

 This appears to be a common fault in hydrometers. 



NO. 1732, VOL. 67] 



Chemical Society. December 17, 1902. — Trof. Emerson 

 Reynolds, F.R.S., president, in the chair. — The following 

 papers were read : — A reagent for the identification of carbamide 

 and of certain other nitrogen compounds, by Mr. H. J. H. 

 Fenton. Among the derivatives of methyl-furfural previously 

 described by the author is one which may be either methyl-furil 

 or the isomeric keione-aldehyde ; this in presence of a trace of 

 acetyl chloride gives with carbamide and monoalkyl carbamidts 

 a brilliant blue colour. — The rate of decomposition ofdiazo-com- 

 pounds, part ii., diazr-compounds of the naphthalene series, 

 hy Messrs. Cain and Nicoll. The reaction is monomolecular, 

 but after a time is not strictly so owing to the formation of azo- 

 colours. — State of carbon dioxide in aqueous solution, by Prof. J. 

 Walker. It is shown that obedience to Ostwald's dilution law 

 in the case of solutions of carbonic acid gas and similar substances 

 affords no evidence as to the amount of real carbonic acid 

 present in solution. — Qualitative separation of arsenic, antimony 

 and tin, by Prof. J. Walker. The mixed sulphides are dis- 

 solved in soda solution and oxidised with sodium peroxide ; from 

 the solution, stannic oxide is precipitated by boiling with am- 

 monium chloride, whilst arsenic and antimony can be separattd 

 in the usual manner. — The hydrates and solubility of barium 

 acetate, by Prof. Walkerand Mr. W. A. Fyffe. The solubility 

 curve consists of three portions, all convex to the axes and repre- 

 senting the solubilities of a trihydrate, monohydrate and anhy- 

 drous salt respectively. — cis-a.nd trans-38 Dimethylglutaric acid, 

 and the separation of the cis and trans forms ot substituted 

 glutaric'acids, by Messrs. J. F. Thorpe and W. J. Young. 

 — Constitution of metallic cyanides, by ]. E. Marsh. Metallic 

 cyanides, with the exception of those ot silver and mercury, are 

 oxidised hy permanganate to cyanates, whence the author con- 

 cludes that in general these cyanides have the isonitrile structure, 

 the exceptions being nitriles. — Auto-reduction of mercury and 



silver cyanides, by Messrs. Marsh and Struthers Note on 



the action of acids on cellulose, by Miss M. Gostling. The 

 black residue formed when cellulose is heated with strong haloid 

 acids closely resembles the artificial humus obtained by the 

 action of dilute acids on sugars. — Nitrotartaric acid and some 

 of its esters, by Prof. P. F. FranklanrJ, Mr. II. L. Heathcote 

 and Miss Hartle. — The nitration of diethylmonobenznyl and 

 mono-/ tolu)l tartrates, by Prof. P. F. Frankland and Messrs. 

 Heathcote and Green. A preliminary description of these 

 derivatives of tartaric acid. — Interchange of halogen for hydroxyl 

 in chloro- and bromo-naphthalenediazonium hydroxides, by Dr. 

 Orton. — Purpurogallin, by Messrs. A. (1. Perkin and A. B. 

 Steven. A description of acyl and alkyl derivatives is given 

 and the products of decomposition by potassium hydroxide are 

 found to be two ketonic substances of the formula C n H 6 5 . 

 — Note on the destructive distillation of ethyl gallate, by 

 Mr. A. G. Perkin. In addition to pyrogallol and ethyl alcohol, 

 there is formed 7 per cent, of rufigallic acid ; the laiter is als. > 

 produced by the distillation of gallic acid itself. — A series of 

 double chromates, by Mr. S. H. C. Briggs. A double salt of the 

 composition (NHj)„Ni(Cr< f l ).,,6H„0 and a second of the com- 

 position (NH 4 ),,Ni(Cr0. 1 ).,,2NH :: have been obtained, as well as 

 the corresponding salts of copper, zinc and cadmium, by the 

 action of ammonia on the appropriate dichromates. 



Linnean Society, December 18, 1902. — Prof. Sydney H. 

 Vines, F.R.S. , president, in the chair. — Notes on some Copepoda 

 from the Faroe Channel, by Mr. Thomas Scott. Waterlogged 

 and partly decayed pieces of wood are frequently brought up in 

 the dredge, and these fragments harbour Entomostraca. In this 

 manner, some of the rare forms, commented on in this paper, 

 were obtained. Three new species and a new variety of another 

 previously characterised species were described. — The Amphi- 

 poda of the Southern Cross Antarctic expedition, with remarks 

 on bipolarity, by Mr. A. O. Walker. The collection was 

 made between Cape Adare in April, 1S99, and Franklin Island in 

 February, 1900, the larger part after the death of the zoologist 

 of the expedition (Mr. N. Hanson) by Mr. Anton Fougner, 

 partly by dredging. The species obtained have a striking 

 resemblance to forms found in Arctic seas, though only one 

 species has been deemed identical, Ampelisca macrocephala, 

 Lilljeb. The author does not put forward any theory of his 

 own to account for the similarity of forms in the Arctic and 

 Antarctic regions, with their absence from the intervening 

 tropical seas, but he adduces many instances of it, especially 

 the distribution of the genus Orchomenopsis, Sars, which is 

 widely spread in waters of low temperature. One new genus, 

 Oradarea, is described with a single species, from Cape Adare. 



