400 RECORD OF SCIENCE FOR 1886. 



by a weighed amount of iron, and a weight of iron fluoride was obtained 

 sensibly corresponding to the weight of tlie hydrogen liberated. 



The isolation of fluorine by M. Moissan was regarded by the French 

 Academy of Sciences as of such prime importance that the subject was 

 referred to a committee for examination. This committee reported 

 through its chairman, M. Debray (on the 8th of November), that they 

 found Moissan's experiments and statements satisfactory in all respects, 

 and that the isolation of the element was undoubtedly an accomplished 

 fact. (Comptes Eendus, cii, 1543, cm, 202, 256, and 850.) 



A Neiv Gaseous Body, Phosphorus Oxyfluoride, by H. Moissan. — The 

 new compound PF3O2 has an experimental density, which oscillates 

 between 3.68 and 3.75. It is instantly absorbed by anhydrous alcohol, 

 by solutions of chromic acid, or by the alkalies. The existence of this 

 compound renders impossible the experiment indicated by Davy, who 

 proposed to isolate fluorine by burning phosphorus fluoride in an at- 

 mosphere of oxygen inclosed in a vessel of fluorspar. Fluorine has the 

 curious property offending always to form ternary or quaternary addi- 

 tion products. (Comptes Kendus, cii, May 31, 1886.) 



The CoTnhiistion of Carbonic Oxide and Hydrogen, by Harold B. Dixon. — 

 The author in 1880 published the fact that a mixture of carefully dried 

 carbonic oxide and oxygen would not explode when electric sparks were 

 passed through it, but that by the addition of a minute trace of water 

 or volatile body containing hydrogen the mixture became inflammable. 

 To account for this fact the author has more recently put forward the 

 hypothesis that the steam acts as the part of a carrier of oxygen, and 

 that it undergoes reduction and successive reformation. Discussion 

 has arisen* as to the mode in which steam exerts its influence, and the 

 author herein gives his reasons for maintaining his hypothesis. 



Experiments were made with small quantities of various gases added 

 to the non-inflammable mixture of dry carbon monoxide and oxygen, and 

 the electric spark passed. In all cases where a gas containing hydrogen 

 was introduced the mixture exploded ; otherwise, not. Steam, therefore, 

 and bodies which form steam under the conditions of the experiment, 

 are alone able to determine the explosion, and it is evident that steam 

 does not act as a mere third body, but in virtue of its own peculiar 

 chemical properties. 



Moritz Traube rejected Mr. Dixon's explanation of the phenomena 

 under consideration, claiming that carbon monoxide does not decom- 

 pose steam at high temperatures, but the author shows that it has been 

 amply proved by different experiments, notably by Naumann and Pistor 

 (Berichte d. chem. Ges., 1885, 2894) that the re-action mentioned does 

 take place. Mr. Dixon also gives experimental data for refuting Traube's 

 view that hydrogen peroxide acts as the carrier of oxygen. 



*See Report ou Chemistry iu Smilhsoniau Report for 1885, p. 651. 



