298 Notice of some Recent 



3 Sesqui-hydret HH Ph A gas not inflammable ; decom- 



posed by light. 



4 Perhydret . H 2 s Ph A gas produed by heat from 



phosphite of lead according to 

 H. Rose * 



IV. New class of Borates. — In a paper published in the 

 Kongl. Vetensk. Acad. Handl., for 1834, a class of simple 

 borates is described. Borax and carbonate of soda were 

 boiled together. An effervescence took place ; the gas which 

 was disengaged was passed through a tube containing lime- 

 water ; a precipitate fell. Hence, the opinion, that borax 

 is a biborate appears correct. Crystallized borax and an- 

 hydrous carbonate of soda were mixed and heated to the 

 melting point of silver, in a platinum crucible ; the mass 

 had lost all the water of the borax and the carbonic acid 

 of the soda, but acquired no appearance of fusion. It was 

 dissolved in water, concentrated, and allowed to crystallize 

 in an air tight vessel. Sharp four-sided prisms appeared 

 with truncated extremities. The angles were 70° and 110°. 

 This salt has an alkaline taste, and absorbs carbonic acid 

 from the air. It melts at 57 C (134°-6 F.) in its water 

 of crystallization, but does not crystallize on cooling. A 

 portion of the salt melted in its water of crystallization 

 remained for many days at the temperature of 32° without 

 crystallizing. 



1-046 grms. of the original crystals of this salt lost by 

 heating 0-502 grm. of anhydrous salt, and lost 0*542 water, 

 which the author considers equivalent to 8 atoms of water 

 and the composition of the salt NaB + 8 HO. 



4-098 grms of the crystallized and melted salt, gave 2'26 

 after heating = 6 atoms of water. 8 atoms are equal to 

 52-11 per cent, and 6 atoms to 44-832 per cent, of water. 



A similar salt is obtained by heating in a white heat 

 boracic acid and carbonate of potash. It dissolves in very 

 little water, and it is, therefore, difficult to obtain it in 

 regular crystals. Solutions of these salts added to neutral 

 solutions of earthy and metallic oxides, precipitate borates 

 of the same composition. — (Poggendorff's Ann. xxxiv. 561.) 



V. Xanthic acid. — This acid may be prepared from the 

 Xanthate of potash by means of sulphuric acid. The Xan- 



■ Ann. de Chim. lx. 17-1. 



