1906.] 



SULPHURIC ACID ON DEPOSITION OF METALS. 



263 



In the presence of two cubic centimeters of acid, after twenty 

 minutes, the solution gave a brown color after adding ammonium 

 hydroxide and ammonium sulphide. In thirty minutes the test 

 showed that there was still a small amount of nickel unprecipitated. 



Fig. 5. Nickel. 



In thirty-two minutes nickel was found in the solution siphoned 

 from the cup. 



In 5 minutes, 0.1265 gram of nickel was deposited. 



Cobalt, 



The solution of cobalt sulphate contained 0.1700 gram of cobalt. 

 Twenty-five minutes were required for its complete precipitation in 

 the presence of one cubic centimeter of sulphuric acid. 



PROG. AMER. PHIL. SOC, XLV. 183Q, PRINTED FEBRV^RY 1 9, I907. 



