Chemistry and Physics. 393 



amorphous, scarcely sweet, unfermen table substance. He as- 

 sumed that the substance consisted chiefly of the anhydride of 

 glucose C 6 H 10 O 5 (that is, C 6 H 12 6 — H 2 0) to which he gave the 

 name glucosane, but he did not succeed in isolating it in a state 

 of purity. Since that time it appears that no further study of 

 the substance has been made until recently when Ame Pictet and 

 Pierre Castan have taken up its investigation. They have 

 found that by slightly modifying the original method of prepa- 

 ration, heating the glucose only to a temperature of 150-155° 

 under a much diminished pressure (15 mm. of mercury), there 

 is a regular disengagement of water without any oxidation or 

 profound decomposition, and after cooling, a nearly colorless 

 solid mass is obtained. The glucosane obtained in this way can 

 be crystallized from methyl alcohol solution, and the authors have 

 confirmed the formula C 6 H 10 O 5 . They have found also that the 

 substance gives interesting reactions, and it is expected that the 

 study of the products will lead to precise conclusions in regard to 

 the structure of the two isomeric glucoses. — Comptes Rendus, 

 171, 243. h. l. w. 



4. A new Method for the Determination of Zirconium. — In 

 view of the difficulties connected with the methods heretofore em- 

 ployed, Melvin M. Smith and C. James have made the applica- 

 tion of selenious acid for the purpose of precipitating zirconium 

 and have found the method very satisfactory. This reagent has 

 the advantage over nitroso-phenyl-hydroxylamine (cupferron) 

 in giving a separation from moderate quantities of iron. It 

 gives also a separation of zirconium from aluminium and the rare 

 earths, and in the presence of an excess of hydrogen peroxide a 

 separation from titanium. The precipitation should be made in 

 hydrochloric acid solution containing not over 7% of the strong 

 acid, and the precipitate is washed with water containing about 

 3% of the acid. It is then ignited and the oxide is weighed. 

 The method does not give a separation from thorium, but this 

 element appears to be absent from most zirconium ores. For 

 the separation from phosphoric acid and for other details the 

 original article must be referred to. — Jour. Amer. Chem. Soc, 

 42, 1764. h. l. w. 



5. The Stability of Sucrose in Acid Vegetable Juices. — H. 

 Colin calls attention to the fact that in many sweet fruits, such 

 as oranges, etc., cane sugar exists in the presence of free acid 

 the concentration of which is more than sufficient to produce the 

 inversion of the sugar to glucose. Many authors have called 

 attention to this circumstance with surprise, and it has even been 

 suggested recently that possibly the sugar and acid might be 

 contained in separate sacs in such fruits. Colin explains this 

 stability on the ground that the acid vegetable juices contain 

 alkaline salts, chiefly potassium salts, of the acids, and that it is 

 well understood that salts of weak acids by their presence greatly 

 diminish the hydrogen ionization of the acids, and consequently 

 their power of inverting sucrose. He has. shown experiment- 

 ally that mixtures of vegetable acids with their potassium salts, 



