OP ARTS AND SCIENCES. 87 



It crystallizes in narrow plates, which not infrequently reach a 

 length of over one centimeter, and are characterized by a well-marked 

 cleavaire at riijht angles to their lonojer axis. On one occasion rhom- 

 bic forms similar to those of the sodium salt of the parachlorbenzyl- 

 sulpho-acid were observed. It is not freely soluble in cold water or 

 alcohol, but its solubility in each of these solvents is much increased 

 by heat. The solubility in water at 18° was determined as fol- 

 lows : — 



I. 3.2760 g. of the saturated solution gave 0.2016 g. of the salt. 



II. 2.7104 g. gave 0.1689 g. of the salt. 



Percentage of CgH^BrCHgSOgK in aqueous solution saturated at 

 18°: — 



T. II. 



6.15 6.25 



To make the other salts of the sulpho-acid, the crude potassium salt 

 was treated with a small quantity of plumbic acetate, to free it from 

 bromide and sulphite ; and, after filtering from the precipitate thus 

 formed, the lead salt was thrown down by adding an excess of plumbic 

 acetate, and purified by crystallization from water. It was then sus- 

 pended in water, and treated with sulphuretted hydrogen to convert 

 it into the free acid, which was used in the preparation of the following 

 salts. 



The Calcium Salt (CgH^BrCH2S0„)oCa, made by warming the acid 

 with calcic carbonate, and purified by crystallization from water, was 

 free from water of crystallization. 



0.4472 g. of the salt dried at 110° gave 0.1096 g. of calcic sulphate. 



0.2870 g. gave 0.0715 g. of calcic sulphate. 



Calculated for (CjHoBrSOjjjCa. Found. 



Calcium 7.41 7.21 7.33 



The salt crystallizes in long colorless plates, and is freely soluble in 

 water. 



The Barium Salt (CgH^BrCH2S03)2BaH20 was made from the 

 acid with baric carbonate, and purified by crystallization from water, 



0.4300 g. of the salt dried in vacuo lost, when heated to 110°, 

 0.0124 g. of water. 



0.4396 g. lost 0.0123 g. of water. 



Calculated for (C7lI„BrS03)2BaH20. Found. 



Water 2.75 2.88 2.80 



