644 ANNUAL RECORD OF SCIENCE AND INDUSTRY. 



acid by simply placing these substances beneath some bodies 

 in a moist condition, and by apjjlying them as a coating to 

 others, with and without paper, potato and wheat starch be- 

 ing employed as pastes. After from eight days to three 

 weeks, in different cases, the presence of arseniureted hydro- 

 gen in the air was unmistakably revealed by tests, and left 

 no doubt that cases of chronic arsenical poisoning must be 

 attributed not only to the mechanical mixture of arsenical 

 compounds with the air of rooms in the form of dust, but 

 also to the presence of this gas, resulting from the decompo- 

 sition of free arsenious acid in Schweini'iirth jxi'een. It was 

 also found that the development of the gas is favored by 

 moisture in the air and the presence of organic matter, espe- 

 cially that in the paste. Mould appeared on the paper in 

 some cases, showing that arsenic is not a preventive of its 

 formation, as often stated. 19 C, January 25, 1873, 35. 



NEW MODE OF TAKING COD-LIVER OIL. 



A novel method of administering cod-liver oil, announced 

 by Carre and Lemoine, consists in introducing it into bread, 

 each pound containing seventy-five grammes (or five tea- 

 spoonfuls) of the oil, and about ninety grammes of milk. 

 This bread is said to be in every respect sweet and palatable, 

 without the least smell or taste of the oil. 12 J5, July 15, 

 1873, 26. 



ELECTRICITY FOR CURING TOOTHACHE. 



Dr. Bouchaud, of Paris, strongly recommends the use of 

 electricity in cases of severe toothache, and maintains that 

 not unfrequently a perfect cure will be efiTected, even Avhere 

 the teeth are greatly decayed. He has seldom failed to se- 

 cure at least a temporary relief, this frequently lasting for 

 days, and often continuing indefinitely. In numerous in- 

 stances where alleviation after the first application was of 

 brief duration, the effect became more and more marked, and 

 lasted longer as the treatment was repeated. The method 

 adopted for applying the electricity is to place the positive 

 pole of the current on the cheek opposite the diseased tooth, 

 and the negative upon the antero-lateral portion of the neck ; 

 and, to avoid ulcerations, he makes the electrodes very large, 

 and changes their place frequently. He continues the appli- 



