July 29, 1922] 



NA TURE 



165 



les-Vierges on a semi-technical scale, and a large 

 factory at Villers-St-Paul, with a contemplated 

 capacity of 4000 tons of synthetic indigo a year. This 

 was abandoned during the German advance in 1918 

 and the material removed to Lyons, but it has again 

 been set in operation, and as a result of intensive 

 work, the total production of the French factories had 

 grown from 175 tons in 1919 to 765 tons in 1920. 

 Since that time the production has decreased on 

 account of the economic crisis, although the capacity 

 of production is now stated to exceed 13,000 tons. 

 With a few exceptions, dyes of all the main types are 

 manufactured and progress is being made. 



The company has two large centres of production. 

 The Oissel Works, installed at the old national factory, 

 with an area of 39,000 sq. m. of buildings, is 

 connected with the main line from Paris to Rouen. 

 The power is generated by turbo-alternators of the 

 most modern type, each of 1000 kilowatts. The 

 factory is at present making intermediates, of which 

 more than sixty are being produced, together with 

 sulphur dyes and azo-dyes. These are produced 

 directly from the intermediates without isolation of 

 the latter from solution. 



The second works is that at Villers-St-Paul, with 

 an area of 35,000 sq. m. of buildings, on the main line 

 from Paris to Compiegne. A very modern boiler 

 plant is installed, which when complete will consume 

 300 tons of coal daily. In this works are made the 

 dyes which require special apparatus, such as indigo 

 and alizarine, phthalic acid and basic dyes derived 

 from it, triphenyl and diphenylmethane dyes, pyr- 

 azolone dyes, etc. Vat dyes are also made, and there 

 are large research laboratories. 



At Saint-Denis the old works has been enlarged, 

 while a new works at Isere grew up during the war. 

 It is stated that prices are now high owing to high 

 costs of raw materials, and the yields could also be 

 improved by the further efforts of the chemists, and 

 particularly of the engineers. 



The Metallic State. 



jD ECENT advances in our knowledge of the 

 A ^- structure of the atom have added very little 

 to the elucidation of the nature of the metallic state, 

 and in this connexion a very suggestive paper by 

 Prof. C. A. Kraus, in the June number of the Journal 

 of the American Chemical Society, will be of interest. 

 According to modern views the metals owe their 

 characteristic properties to the presence of negative 

 electrons free to move within the body of the metal. 

 Electronegative elements, such as chlorine, owe their 

 characteristic property of forming anions to the 

 fact that they are capable of forming stable complexes 

 (the ions) with one or more negative electrons. 

 Metallic properties may be expected only in such sub- 

 stances as do not contain sufficient electronegative 

 elements to engage the negative electrons supplied 

 by the more electropositive constituents, or other- 

 wise, in which electronegative elements are lacking. 

 The smaller the affinity of an element or group for 

 the negative electron, the more electropositive will 

 it appear, and the more readily will it enter into 

 reaction with more electronegative elements. 



The association of negative electrons with positive 

 metallions, which is supposed to make up the structure 

 of a metal, has some resemblance to a salt. At 

 very low concentrations the negative electron may 

 no longer possess the freedom of motion characteristic 

 of the metallic state, and it is known, for instance, 

 that mercury vapour is a very poor conductor. The 

 metal may under such conditions exhibit salt-like 



properties, and intermetallic compounds may also 

 show resemblances to salts. There are many such 

 compounds which have properties in harmony with 

 this view. The more electronegative elements in 

 such compounds are supposed to have a negative 

 charge. The compound Na 3 Sb is then similar to 

 Na 3 N or Na 3 P. The question is raised whether the 

 apparent deviations of intermetallic compounds from 

 the valency relations may not be due to the tendency 

 of electronegative elements to form complexes. 

 This is shown in the compounds NaN 3 , KI 3 , etc., 

 and it is suggested that something of the kind occurs 

 in such compounds as Na,Sn, Na 2 Sn, Na,Sn 3 , NaSn, 

 and NaSn 2 . The atoms in such complexes, however, 

 may not all function in the same manner. The 

 property of metallicity is not an atomic one ; it 

 is due to the negative" electron, and the role of the 

 positive constituent is a secondary one. 



Many reactions in liquid ammonia solution, and the 

 existence of substituted ammonium amalgams and 

 substituted ammonium radicals in liquid ammonia 

 solution, support the views expressed. As an 

 example it is stated that tellurium reacts with a 

 solution of sodium in liquid ammonia to form a white 

 crystalline precipitate of the typical salt-like com- 

 pound Na 2 Te. On further addition of tellurium this 

 goes into solution with the production of complex 

 tellurides, Na^e. and Na 2 Te 4 , which form strongly 

 coloured solutions, similar to those of alkali-metals, 

 and when precipitated from solution exhibit metallic 

 properties. 



University and Educational Intelligence. 



London. — At a meeting of the Senate on July 19, 

 Dr. J. C. Drummond was appointed to the University 

 chair of biochemistry tenable at University College. 

 Dr. Drummond graduated from East London College 

 with first-class honours in chemistry, and has been 

 research assistant in the Physiological Laboratory 

 at King's College and assistant analyst in the Govern- 

 ment Laboratory (Foods Department). He has also 

 conducted research work at the Cancer Hospital, and 

 has been since 1920 University reader in physiological 

 chemistry at University College. 



Prof. Adrian Stokes was appointed to the Sir 

 William Dunn chair of pathology tenable at Guy's 

 Hospital Medical School. Prof. Stokes has held 

 the posts of assistant to the professor of pathology 

 at Dublin University and pathologist to the Royal 

 City of Dublin Hospital, while since 1919 he has been 

 professor of bacteriology and preventive medicine 

 at Dublin University. Two years ago he worked 

 with the Rockefeller Commission on Yellow Fever 

 in Nigeria. 



The following doctorates were conferred : — D.Lit.: 

 Mr. W. I. Moore, King's College, for a thesis entitled 

 " Education and Social Systems, English and French : 

 A Study of Educational Effort and Opinion 1750- 

 1810"; D.Sc, in Botany: Miss Dorothy Haynes, 

 King's' College and the Imperial College — Royal 

 College of Science, for a thesis entitled " (1) Electrical 

 Conductivity as a Measure of the Content of Electro- 

 lytes of Vegetable Saps, and (2) the Action of Salts 

 and Non-electrolvtes upon Buffer Solutions and 

 Amphoteric Electrolytes and the Relations of these 

 Effects to the Permeability of the Cell " ; D.Sc, in 

 Physics : Mr. W. E. Curtis, King's College, for a 

 thesis entitled " The Structure of the Band Spectrum 

 of Helium " ; Mr. B. A. Keen, University College, for 

 a thesis entitled " The Physical Properties of Soil " ; 

 Mr. F. H. Newman, for publications entitled "Active 

 Modification of Hydrogen and Nitrogen produced by 



NO. 2752, VOL. I IO] 



