SULPHURETTED HYDRO-SULPHURETS, 349 



3. The color varies in intensity according to the degree of con- 

 centration. 



4. The principal use made of this preparation is in eudiometry ; 

 but the compound with lime is most used, which see. 



SULPHURETTED HYDRO-SULPHURET OF SODA. 



1 . It is almost perfectly identical with the last. 



2. The sulphate may be decomposed by charcoal in the same 

 manner, but the appearances are less striking. 



SULPHURETTED HYDRO-SULPHURET OF AMMONIA. 



1. If liquid ammonia be digested upon sulphur, the action is fee- 

 ble and not much sulphur is dissolved. 



2. But ammonia in its nascent state, dissolves sulphur readily. 



3. A preparation of this kind was formerly called Boyle's fuming 

 liquor ; 3* parts slacked lime, 1 muriate of ammonia, 1 flowers of 

 sulphur, and half a part of water, are mingled and a gentle heat ap- 

 plied ; the first drops are watery, and as they become deeper colored, 

 the heat is raised till the bottom of the retort becomes slightly red. 



4. White fumes are abundantly extricated in the more early stages 

 of the operation, and must have vent from the receiver. 



5. The fumes may be all collected in a Woulfe's apparatus; they 

 are more abundant and incoercible in proportion as less water is 

 added. 



6. The liquor fumes, as soon as the stopper is withdrawn from the 

 bottle in which it is kept. 



7. The fuming is owing to the ammonia in excess, meeting with 

 sulphuretted hydrogen,f for when the fuming liquor is digested on sul- 

 phur, the ammonia becomes saturated and the fuming ceases. 



SULPHURETTED HYDRO-SULPHURET OF LIME. 



1. Boil slacked lime with JJ sulphur and 10 parts of water, for 

 half an hour or an hour, and shake frequently during the boiling. 



2. The fluid is of a fine orange yellow, and deposits crystals one 

 cooling. 



3. Decomposition of the sulphate by charcoal and heat, succeeds 

 but imperfectly. 



4. For the rest, see general properties. 



5. This preparation and the parallel one of potassa are much used 

 in eudiometry, and this is rather preferred, because it affords the 

 most concentrated solution. 



* 1, Ure. 



\ Proceeding, doubtless, from the decomposition of water, by the compound of am- 

 monia and sulphur. 



t Equal weights of lime and sulphur. Murray, This is much more sulphur 

 than is needed. 



