July 23, 1903] 



NATURE 



285 



one of the enantiomorphously related configurations ; all 

 'the albumins are IzEvo-rotatory, all the starches and sugars 

 are derived from dextro-glucose. Since Fischer's work 

 teaches us that none of the sugars derived from Isevo- 

 glucose are fermentable by yeast, it would seem to follow 

 as a legitimate conclusion that, whilst d-glucose is a 

 valuable food-stuff, we should be incapable of digesting its 

 ■enantiomorphously related isomeride, J-glucose. Humanity 

 is therefore composed of dextro-men and dextro-women. 

 And just as we ourselves would probably starve if provided 

 with nothing but food enantiomorphously related to that 

 to which we are accustomed, so, if our enantiomorphously 

 related isomerides, the laevo-men, were to come among us 

 now, at a time when we have not yet succeeded in preparing 

 synthetically the more important food-stuffs, we should be 

 unable to provide them with the food necessary to keep 

 them alive. 



CHLORINE SMELTING, WITH 

 ELECTROLYSIS. 



A PAPER on chlorine smelting with electrolysis was 

 ■^ read by Mr. Swinburne at the first meeting of the 

 Faraday Society ; as the process described in the paper is 

 of considerable interest, and may one day be of great im- 

 portance, we give a brief abstract of the paper below. 



The process is one for the treatment of complex sulphide 

 ores, such, for example, as the Broken Hill slimes, and is 

 ■divided into three stages as follows : — (i) the treatment of 

 the ores with hot chlorinfe, whereby the metals are all 

 obtained as chlorides ; (2) the treatment of the mixed 

 chlorides by substitution until finally all the chlorine is 

 combined with zinc ; and (3) the electrolysis of the zinc 

 chloride to extract the zinc and recover the chlorine. The 

 first stage of the process is carried out by blowing hot 

 chlorine into the crushed ore in a "transformer"; the 

 essential feature is to avoid the formation of chloride of 

 «ulphur. 



This involves a careful regulation of temperature and of 

 the rate of feed of the ore ; the temperature can be 

 easily regulated by the rate of feed of the ore and chlorine 

 as the reaction evolves a great deal of heat, and the trans- 

 former is entirely self-heating. Advantage can be taken 

 of the composition of the ore, as some of the metals have a 

 greater heat of reaction than others; if necessary, a mixture 

 of ores of different compositions can be made so as to give 

 a satisfactory working material. The sulphur is set free 

 and condensed. At the end of a charge the ore feed is 

 stopped, and the excess of sulphides converted to chlorides, 

 after which the fused chlorides are drawn off and dissolved ; 

 the gangue having been separated by filtration, the second 

 part of the process begins. This naturally depends on the 

 composition of the ore ; lead, silver, and gold are separated 

 with the gangue, and after drying are fused first with lead, 

 which e.xtracts the silver and gold, and then with zinc, 

 which gives lead and zinc chloride, the former practically 

 pure. The filtrate is treated with spongy copper to separate 

 lead and silver, and then with zinc to take out the copper. 

 Iron, manganese, and zinc chlorides are left; the iron is 

 chlorinated up to the ferric state, and precipitated as ferric 

 hydrate by zinc oxide, and further chlorination in presence 

 of the zinc oxide throws down the manganese as peroxide. 

 There is thus left only zinc chloride in solution, and this 

 is evaporated down and fused. To it is added the fused 

 chloride from the lead substitution, and the whole is 

 electrolysed in vats made of iron lined with fire-brick. The 

 heating is internal ; the current and the chloride soaking 

 into and solidifying in the fire-brick gives really a vat with 

 zinc chloride walls. Vats taking 3000 amperes have been 

 in use, but these are small, and 10,000 ampere vats are to 

 bo tried ; the pressure required is less than four volts. The 

 result of the process is pure zinc and chlorine ready for 

 chlorination of fresh ore. 



It will be seen that the chief merits of the process are 

 its comprehensiveness, its cyclical nature, and the fact that 

 it turns out pure metals. Obviously it is suited, with only 

 •flight modifications, for the treatment of a great variety 

 t ores. The chlorine simply goes round and round ; apart 

 rom leakage, which, as Mr. Swinburne says, if it would 

 ■how on the balance sheet would make the works uninhabit- 



NO. 1760, VOL. 68] 



able, chlorine can only be lost as chloride of sulphur (a 

 source of loss the inventors claim to have overcome), and 

 a? oxychlorides formed in the iron separation and in 

 evaporation of the zinc chloride, neither of great import- 

 ance if care be taken. The works therefore simply take in 

 ore and electrical energy and turn out metals, sulphur, and 

 gangue. Mr. Swinburne enters at some length into the 

 question of cost, but space does not permit of our follow- 

 ing him here ; we have said enough to indicate the interest- 

 ing character of the paper, to which those more specially 

 interested mav be referred for further details. 



M. S. 



T//E ROYAL INSTITUTE OF PUBLIC 

 HEALTH. 

 HTHE annual congress of the Royal Institute of Public 

 ■*■ Health was held at Liverpool, July 15-21, under the 

 presidency of the Earl of Derby. The sections met in the 

 various departments of the University College, and were 

 thus closely associated and readily accessible. The proceed- 

 ings were opened by an interesting address from the Earl 

 of Derby, in which he directed attention to the considerable 

 progress in sanitation that had been made by many ancient 

 civilisations. The Harben medals for 1901 and 1902 were 

 then presented to Sir Charles Cameron and Prof. W. R. 

 Smith. 



A combined conference of the preventive medicine and 

 municipal hygiene sections discussed the subject of tuber- 

 culosis, and Dr. Nathan Raw read a paper upon " The 

 Prevention of Consumption in Large Cities," in which he 

 expressed the opinion that consumption is frequently con- 

 veyed to children by milk from tuberculous cows, though 

 patients in the advanced stage are the greater source of 

 danger to the community. He suggested as means for 

 controlling the disease (i) the establishment of a central 

 office where consumptives might seek advice ; (2) the erection 

 of a municipal sanatorium which, for Liverpool, should 

 contain 100 beds, and be within the reach of any needy 

 citizen ; and (3) the foundation of a hospital for the poor 

 for at least 100 incurable cases. Several other papers deal- 

 ing with tuberculosis were also contributed ; one, by Mr. 

 McLauchlan Young, who summarised the experiments per- 

 formed by Prof. Hamilton and himself upon the com- 

 municability of bovine tuberculosis to man, and expressed 

 the opinion that there could be little doubt that human 

 tubercle can be readily inoculated upon bovines ; another, by 

 Drs. Dean and Todd, upon the communicability of human 

 tuberculosis to the pig, in which the six animals experi- 

 mented upon were all infected with the human bacillus. 

 Thus there is already an accumulation of evidence against 

 the view expressed by Koch at the Tuberculosis Congress 

 of 1901, that bovine tuberculosis is probably not com- 

 municable to man. 



In the section of bacteriology and comparative pathology, 

 the president. Prof. Boyce, F.R.S., in his opening address 

 directed attention to the connection between abstract re- 

 search and the good of the community, instancing the value 

 of bacteriological research to practical medicine, to the 

 farmer, to the water engineer, and to the oyster merchant. 

 A paper by Dr. Savage upon " A Uniform Method of Pro- 

 cedure for the Bacterioscopic Examination of Water," 

 evoked an interesting discussion. He considered the subject 

 under four headings : — (i) the methods of collection and 

 transmission of the samples ; (2) the data which it is desir- 

 able to ascertain ; (3) the processes and procedures of the 

 examination ; and (4) the significance to be attached to the 

 results obtained. It was ultimately resolved to form a 

 committee to consider whether it might not be possible to 

 systematise the methods, &c., to be used for the bacterio- 

 logical examination of water. 



Another important discussion, upon " the nature and sig- 

 nificance of the pseudo-diphtheria bacillus," was opened by 

 Dr. Cobbett, who expressed the opinion that this organism 

 has nothing whatever to do with the true diphtheria bacillus. 

 Prof. Hewlett stated that he was not yet convinced that the 

 two organisms had no connection, and directed attention to 

 several points of similarity between the two. Several 

 medical officers of health held that, whether the two 

 organisms had any connection or no, the pseudo-bacillus 

 sometimes produced a diphtheritic condition. It is im- 



