50 Mr. A. Dick's Analysis of Hayesine. 



great additional resistance if a portion of it took the outer arms 

 of the cross for its path, and consequently we should look for a 

 diminished action in the galvanometer when the arms are so 

 different ; yet in the trial I made, I found the induced current 

 in the long arms apparently exalted above the effect derived from 

 a similar cross of equal arms of 2 inches long in each arm. 



VI. Analysis of Hayesine. By Allan Dick, Esq., Metallur- 

 gical Laboratory } School of Mines*. 



THIS mineral occurs in the nitre beds of Peru, often in the 

 form of rounded masses about the size of a walnut, com- 

 posed of interlacing silky crystalline fibres. If kept in a closed 

 vessel a short time, it emits a slight odour like that of iodine, 

 but distinct from it. It showed no action on a piece of starch 

 paper which was enclosed for twenty-four hours in the bottle 

 containing it (it may possibly be due to some compound of iodine 

 or chlorine and oxygen). It has been described by Ulex {Ann. 

 Phann. lxx. 49) who assigned to it the formula of NaO, 2CaO, 

 5B0 3 + 10 aq. In Peru it is known by the name of Tiza. 



15*60 grains were dissolved in dilute hydrochloric acid, and 

 filtered from a few sandy particles which weighed 0*05. 



The lime was precipitated as oxalate, filtered off, and converted 

 into carbonate by ignition, which weighed 3*97. 



Hydrochloric acid and chloride of barium were added to the 

 filtrate ; the sulphate of baryta obtained weighed 0*50. 



10'53 grains were dissolved in dilute nitric acid, filtered, and 

 nitrate of silver added ; the chloride of silver weighed 0*69. 



10*86 grains were mixed with about 25 of pure fluor spar in 

 a platinum crucible, drenched with sulphuric acid, and heat 

 applied till the excess of acid was expelled ; the residue was dis- 

 solved in hydrochloric acid, and chloride of barium added ; the ex- 

 cess of baryta was precipitated from the filtrate by carbonate of 

 ammonia, and the alkalies determined in the usual manner, 

 weighed as chlorides ; the potash was estimated by bichloride of 

 platinum. 



Weight of mixed chlorides . . . 2'06 

 Weight of potas. chlor. of platinum 0*29 



5*40 grains were mixed with some dry carbonate of soda and 

 placed in a small tube closed at one end ; this was connected 

 to a weighed chloride of calcium tube, and the heat of a spirit- 

 lamp was applied to the tube containing the mixture. 



Weight of water 1*47. 



Communicated by the Author. 



