MICROCHEMISTRY. 



145 



phuric acid, which in concentrated solution throws out 

 short orthorhombic crystals of anhydrous calcium sul- 



FiG. 54. — Crystals of Cesium Alum. (After Lehmann.) 



phate. From dilute acid solutions slender monoclinic 

 prisms of the compound (CaS04+ 2H2O) crystallize out 



Fig. e,e,. — Crystals of Calcium Sulphate. (After Lehmann.) 

 (Fig. 55), showing numerous double twins, as at C, 

 and in presence of strong acids, masses of minute needle- 

 like crystals, as at .4. 



