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LXV. Intelligence and Miscellaneous Articles. 



ON THE ABSORPTION OF OZONE BY WATER. BY L. CARUS *. 



OZONE has generally been considered insoluble in water. Mean- 

 while M. Soret has announced its absorption by that liquid ; 

 vet hitherto nothing positive is known on the subject. 



It is easy to ascertain that water into which ozonized air or 

 oxygen has been made to pass exhibits all its reactions : it decom- 

 poses iodide of potassium, decolours indigo and the sunflower, 

 colours blue the tincture of guaiacum, transforms the protoxides of 

 thaUium, manganese, and lead into peroxides ; by its action on 

 silver one sometimes even succeeds in determining the formation of 

 the peroxide of that metal. The author has, besides, proved that 

 this water contains neither oxygenated water nor nitrous acid, either 

 free or combined with ammonia, the presence of which might have 

 explained at least a part of these reactions. 



The power of absorption of ozone in water cannot be determined 

 with precision, because we can only operate on mixtures in which 

 that gas is only in a very small and never very constant proportion. 



In his experiments, the author produced ozone by Soret's method 

 — that is to say, by electrolysis of sulphuric acid spread out and kept 

 at the temperature of zero C. In these conditions the proportion of 

 ozone in the gas, determined by the decomposition of iodide of potas- 

 sium, was found in two trials to be 0'93 and \'2\ volume per cent., 

 supposing this gas to have a density equal to f of that of oxygen. 



The gas was caused to pass during from two to three hours into 

 water kept between 2° and 4° ; it was then submitted to analysis, 

 and was found to contain per litre, in three experiments : — 



0-0109 gramme of ozone, or 5T1 cub. centims. 



0-0094 „ „ 4-24 



0-0083 „ „ 3-86 



The author likewise analyzed the ozonized water supplied by the 

 works of MM. Krebs, Kroll & Co., of Berlin, for medical uses. 

 He found in it from 4-06 to 4'45 cubic centims. of ozone per litre ; 

 it, too, contained neither oxygenated water, nor nitrous or nitric 

 acid. — Bihl, Vniv., Arch, des Sciences, vol. xliv. p. 348. 



ON THE HEAT OF EXPANSION OF SOLID BODIES, BY H. BUFFf. 



The augmentation of volume undergone by a solid body by 

 heating is most analogous to the extension produced by the traction 

 of a weight. Moreover one is naturally induced to seek the quantity 

 of the pressure, or of the force of extension, exerted by heat upon 

 the unit of surface. The solution of this question can be found, if 

 we have, besides the coefficient of expansion of a body, its coefficient 

 of traction, both referred to the unit of volume. 



Now the coefficient of traction of a certain number of bodies in the 

 direction of their length is known ; but the extensibility and com- 

 * BericJite der deufscJien cJierniscJien GesellscJioft, IS7'2, p. 520. 

 ^ Pogg. Ann. vol. cxlv. p. 626. 



