EEVIEW — TEOPICAL MEDICINE, ETC. 165 



77 volumes. This process effectually kills the rodents without injuring the merchandise carried on vessels, but it Plague — 



has disadvantages. It requires costly apparatus and a prolonged exposure to the gases — not less than 24 hours. conlimiM 



Further, it is dangerous to man, while it does not destroy insects. The use of carbon dioxide alone has been 



abandoned owing to its high price. In France preference is given to a mixture of sulphurous and sulphuric acid 



gases, obtained by the free combustion of sulphur in air, but M. Bonjean's experiments have shown that sulphurous 



acid alone, in the proportion of 60 to 80 grammes of the gas per cubic metre, destroys rats almost as quickly 



without exciting so destructive an action upon merchandise. It is important to avoid humidity in the air as much 



as possible and to drive out the residual gas after the rats have been killed. In actual practice the gas may be 



produced by the Marot apparatus, using 70 grammes of liquefied sulphurous acid per cubic metre, or by the 



Clayton or Gauthier-Deglos apparatus, using .35 grammes of sulphur per cubic metre. After two hours the remaining 



gas is removed by ventilators and the dead rats are burned or thrown overboard. 



Leishmani records the views recently advanced at Berlin. Giemsa held that it was 

 absolutely, necessary that all ships which had anchored at plague-infected ports, or had taken 

 cargo from them, should have all the rats destroyed by some sure means, so that none should 

 be free to get ashore at a new port and infect the rats of that port. The ideal gas for this 

 purpose has not yet been discovered, but, after mentioning the disadvantages of liquid 

 carbonic acid gas and sulphurous acid as used in the Clayton process, he recommended that 

 already mentioned under "Disinfection" {page 44), and which consists of carbonic oxide 

 5 per cent., carbonic acid 18 per cent., and nitrogen 77 per cent. Its advantages are — (1) it 

 is devoid of smell and of chemical activity, and is thus little likely to damage cargo ; 

 (2) it is very deadly to rats and certain to kill all of them on board ; (3) it is relatively 

 cheap and can easily be produced in very large quantities, so that even large ships can 

 be filled with the gas in a few hours. 



Tjaden pointed out that its failure to kill fleas constituted a grave defect, and thought 

 that in many cases a sulphur process might be preferable. 



There is little to be said about the treatment of plague, which still remains more or less 

 symptomatic, but Elliot- speaks well of collargol, an allotropio form of silver. It is soluble 

 in water about 1 in 2.5. He used it in intravenous injections, 1 c.c. of a 1 per cent, solution, 

 and he thinks the drug merits further trial. 



ChoksyS writes on recent progress in the serum-therapy of plague and concludes that in 

 Yersin-Eoux anti-plague serum we possess a useful and efficacious remedy against plague. 

 He points out that the absence of all antitoxic action is responsible for its limited utility. 

 The whole secret of the treatment lies in applying the serum very early. Indeed, after the 

 lapse of 48 hours it does not appear to influence the course of the disease perceptibly. It 

 would seem also that the action of the serum is more beneficial after protective inoculation. 



Relapsing Fever. See " Spirochaetosis " (page 185). 



Scorpion Sting. Scorpions are common in the Sudan, and cases of scorpion sting 

 by no means rare. Professor Werner, of Vienna, has kindly furnished me with the following 

 list of the species of Sudanese scorpions identified up-to-date by Dr. A. Birula of 

 St. Petersburg. 



1. Prionurus (Butlius) amoiireiixi, Savigny ; the big, yellow, thick-tailed scorpion of the 

 Northern Sudan deserts. The crests of the upper side of the last segments of the tail are 

 toothed and strongly raised. In the next species they are smooth and feebly raised. 



2. Biithiis quiuquestriatiis, Hemps and Ehrenbg. ; the smaller, yellow species with the 

 tail more or less blackish at the end. It is the most common species, and is found in 

 gardens in Khartoum. 



3. Hottentotta (Biithus) minax, C. L. Koch ; a brownish species found in the Southern 

 Sudan on the White Nile. 



Some statistics regarding scorpion sting in the Sudan are available. Bray in 1902 

 reported twenty-one deaths from this cause : the age distribution being, under 1 year, five ; 

 from 1 to 5 years, nine ; from 5 to 15 years, seven. 



In 1900, forty cases of deaths were known, one being that of a young adult aged 

 18 years. In the 1898 Sudan campaign, a British soldier was killed by a scorpion which 

 stung him several times in the back. 



1 Leishman, W. B. (April, 1908), " The International Congress of Hygiene, Berlin, Sept., 1907." Journal 

 of the Royal Army Medical Corps, Vol. X. 



' Elliot, A. M. (August 17tb, 1907), "Some Remarks on Plague." Lancet, Vol. II. 



» Choksy, N. H. (May 30th, 1908), " On Recent Progress in the Serum-Therapy of Plague." BritUh Medical 

 Journal, Vol. I. 



