318 Scientific Intelligence. 



the tube. The products escaping from the tube contained no car- 

 bon dioxide, but consisted chiefly of carbon monoxide and hydro- 

 gen, with a little propylene and oxygen. The original mixture 

 of gases could not be exploded by an electric spark, but combus- 

 tion gradually took place on continued sparking. When 28 cc 

 were thus treated until no further change in volume took place, 

 there remained 25'15 cc . The original gas contained 4 CC of propyl- 

 ene, but only enough oxygen to burn 2 ,; 7 CC to carbon monoxide 

 and water according to the equation, 



C 3 H 6 + 30 2 = 3CO + 3H 2 0, 



from which it is to be observed that, since the water is condensed, 

 the contraction would correspond to the volume of the propylene 

 thus burnt. The calculated contraction 2'7 CC corresponds very 

 closely with that actually observed, 2*85 cc , so that it is evident 

 that very little of the hydrogen in the mixture was oxidized. — 

 Zeitschr. physikal. Chem., xxxvi, 225. h. l. w. 



3. A Peculiar Blue Color produced when Potassium and 

 Sodium Sulpho cyanides are Heated. — It has been noticed by 

 W. B. Giles that the sulphocyanides under consideration become 

 intensely blue when they are heated to low redness. Upon cool- 

 ing, the color disappears, and it maybe repeatedly produced with 

 the same sample if care is taken not to decompose the substance 

 to too great an extent. If the salts contain much alkaline car- 

 bonate or hydroxide as impurity, the color does not make its 

 appearance. The author is unable to explain fully the cause of 

 the reaction, but believes that it is in some way connected with 

 the liberation of sulphur by the decomposition of the sulphocyanide. 

 He finds, however, that the addition of an excess of the sulphur 

 destroys the color. — Chem. News, lxxxiii, 61. h. l. w. 



4. A Method of obtaining Crystals of difficultly Crystalliza- 

 ble Substances. — A. Rtjmpler gives the following method of crys- 

 tallizing substances which are soluble in water, but insoluble in 

 alcohol: The substance is dissolved in water, alcohol is added 

 until a slight turbidity is produced, when the latter is removed 

 by filtration or the addition of a few drops of water. The clear 

 solution is then placed in a desiccator over quick-lime. Since the 

 lime absorbs water, but not alcohol, the liquid becomes stronger 

 in alcohol as evaporation goes on, instead of losing alcohol more 

 rapidly than water, as would be the case in evaporating in the air 

 or over sulphuric acid, this leads to the crystallization of the sub- 

 stance in case it is capable of forming crystals. — JBerichte, xxxiii, 

 3474. h. l. w. 



5. The ^Elimination of Methane in the Atmosphere. — It is well 

 known that considerable quantities of methane, or marsh gas, are 

 continually passing into the atmosphere, particularly from the 

 fermentation in the absence of air of substances containing cellu- 

 lose. Since there is no considerable accumulation of this gas in 

 the air, it is evident that it must be removed therefrom in some 

 manner. V. Uebain has studied this matter and has found in the 



