ORDER IV. GENERA AND SPECIES. 403 



Expansible : odour sulphurous. 

 Liquid : taste strongly acid. 



1. GASEOUS. Expansible. 



G. = 0-0028. 



Aeriform Sulphuric Acid. J. ii. 23. 



2. LIQUID. Liquid. 



G. = 1-8 ... 1-9. 



Liquid Sulphuric Acid. J. ii. 24. 



IV. BoRAcic-AciD. Solid. 



G. 1-4 ... 1-5. 



1. PRISMATIC. Prismatic. 



Taste acidulous, afterwards bitter and cooling, lastly 



sweetish. 

 G. = 1-4 ... 1-5. 



Sassolinc, ii, 25. 



V. ARSENIC-ACID. Solid. 



G. above 3-0. 



1. OCTAHEDRAL. Tessular. 

 Cleavage, octahedron. 

 Taste sweetish astringent. 

 H. = 1-5. 

 G. = 3-6 ... 3-7. 



Octahedral Arsenic-Acid. J. ii. 26. 



IV. ORDER. SALT 



I. NATRON-SALT. Prismatic. 

 Taste pungent, alealine. 

 H. = 1-0 ... 1-5. 

 G. = 1-4 .., 1-6. 



