Chemistry and Physics. 195 



tact with water. When a mixture of lime and silica in molecular 

 proportions was heated in the electric furnace a crystalline mass 

 of calcium metasilicate CaSi0 3 was obtained, which yielded 

 gelatinous silica with hydrogen chloride and did not set when 

 ground and mixed with water, either alone or mixed with lime. 

 A mixture in the proportion of (CaO) 2 : Si0 2 is more refractory 

 in the furnace, though it yields ultimately a compact crystalline 

 mass of calcium orthosilicate Ca 2 Si0 4 , which placed in a dessica- 

 tor, spontaneously disintegrates to a white amorphous powder. 

 The salt itself gives gelatinous silica with hydrogen chloride and 

 does not set with lime. When a mixture in the proportion of 

 (CaO) 3 : Si0 2 is thus heated, a crystalline mass results which has 

 the approximate composition Ca 2 Si0 4 . CaO, and which disinte- 

 grates spontaneously like the orthosilicate, the result being a mix- 

 ture of lime with the orthosilicate. This material also does not 

 set with lime, and gives gelatinous silica with hydrogen chloride. 

 Similar results are obtained when the CaO is to the Si0 4 as 6 is 

 to 1. It appears therefore that whenever silica is heated with 

 excess of lime combinations occurs only in the proportion needed 

 to form orthosilicate. — Real. Accacl. Line. V., v, 361 ; J. Ch. Soc, 

 lxxiv, 219, May, 1898. G. f. b. 



5. On Ammonium Peroxide. — In investigating peruranic acid, 

 Melikoff and Pissakjewski concluded that its salts were com- 

 pounds of peruranic acid with metallic peroxides; and hence that 

 the hydrogen ammonium salt must contain ammonium peroxide. 

 When a concentrated ethereal solution of hydrogen peroxide cooled 

 to —20° is made to act on an ethereal solution of ammonia equally 

 cooled, a heavy viscous liquid separates, having a faint odor of 

 ammonia, and being strongly alkaline. With potassium hydrox- 

 ide it yields ammonia and potassium peroxide. It irritates the 

 skin, producing white stains. When the ethereal solution is cooled 

 in solid carbon dioxide, acicular leaflets separate having the 

 composition (NH 4 ) 2 2 . (H 2 2 ) 2 . (II 2 O) 10 . A better yield is 

 obtained when the ethereal mixture is placed in a freezing 

 mixture of snow and calcium chloride. Crystals then separate 

 having the composition (NH 4 ) o o . H 2 o . H„(j. They are unstable 

 and deliquesce at the ordinary temperature, first yielding ammonia 

 and hydrogen peroxide, and then evolving oxygen with a little 

 ammonium nitrite. The crystals readily abstract carbon dioxide 

 from the air. They dissolve in alcohol, less readily at —30°. 

 With peruranic acid, they give (NEF 4 ) a 2 . (U0 4 ) a . — Per. Perl. 

 Chem. Ges., xxx, 3144, January, 1898; xxxi, 152-154, February 

 1898. G . F. B. 



6. On the Molecular Masses of Ptorganic Salts. — Aided by 

 four of his students, Werner has determined the molecular 

 masses of a number of inorganic salts by the rising of the boiling 

 point of an organic solvent, selected so that no dissociation would 

 be expected. Many nitrogen and sulphur compounds were found 

 suitable as solvents, piperidine, pyridine, benzonitrile, methyl, 

 sulphide and ethyl sulphide being actually employed, the inor- 

 ganic salts experimented with being for the most part the halogen 



