194: Scientific Intelligence. 



phenylmethane, desoxybenzoin, benzil and as a decomposition- 

 product, benzaldehyde. No gas is yielded by benzoylacetone at 

 300°. Carbon monoxide, pure and carefully freed from oxygen, 

 does not react at 250° with water vapor, but does react at 300°, 

 giving carbon dioxide. So that it seems probable that the for- 

 mation of carbon dioxide in the various decompositions above 

 mentioned is due to a secondary reaction between carbon mon- 

 oxide, the primary product, and the vapor of water. — Ber. Berl. 

 Chem. Ges., xxx, 2921-2926, December, 1897. G. f. b. 



3. On Osmotic Pressure and Electrolytic Dissociation. — The 

 conclusion had been reached by Traube some time ago that the 

 contraction which takes place on the solution of a substance in 

 water is proportional to the concentration of the solution, and is 

 almost independent of the nature of the dissolved substance. 

 This contraction has a value of about 13-5 CC for every dissolved 

 gram-molecule of a non-electrolyte or for every dissolved gram-ion 

 of an electrolyte. This contraction in aqueous solutions is con- 

 jectured to be due to the strong attraction between the solvent 

 and the dissolved substance ; and this suggests the hypothesis of 

 a union (though a changing one) between the water and the sub- 

 stance which is dissolved. The number of water particles with 

 which a given molecule of a substance in dilute solution com- 

 bines, is equal for all non-electrolytes, and for dissolved electro- 

 lytes increases proportionally to the number of ions. From this 

 fact, Van't Hoff's conclusion, that the osmotic pressure of a solu- 

 tion is equal to the pressure which the dissolved substance in the 

 form of a gas would exert at that temperature, may be deduced. 

 Use is made however, in this deduction, of the hypothesis that a 

 molecule of any non-electrolyte in any dilute- solution at any 

 given moment is in union with only one particle of the solvent. 

 The author shows that his views and those of Poynting accord 

 better with observed facts than do the ordinary views of osmotic 

 pressure. The following facts find in them their explanation: (1) 

 Molecular weights vary, as determined in different solvents, (2) 

 colloidal substances have an osmotic pressure equal to zero, or 

 nearly so, (3) the course of any given reaction depends largely 

 upon the nature of the solvent employed, as shown by Menschut- 

 kin, and (4) the fact of sugar inversion and analogous processes. 

 Arrhenius's hypothesis of electrolytic dissociation is considered 

 entirely superfluous. The view of the author is that in dilute 

 solutions, of sodium chloride for example, one molecule of the 

 salt is joined to two of water; while in concentrated solutions 

 they are united one to one. — Ber. Berl. Chem. Ges., xxxi, 154- 

 159, February, 1898. g. f. b. 



4. On Fusion in the Electric Furnace. — The effect produced by 

 heating lime mixed with varying proportions of silica in the elec- 

 tric furnace has been investigated by Oddo. He used an alter- 

 nating current of 120 amperes under a pressure of 40 volts. 

 When granular lime alone was employed, which as is well known 

 readily combines with water, a mass of crystalline scales was 

 obtained which did not slake until alter two or three days con- 



