254 EXAMINATION OF SALT OF BITUMEN* 



which exifted Sulphur was therefore the compound which muft have beeil 



jnafu! P hurctofp re f ent anc j tf WQ are perm i ttec i to rea fon from the pheno- 

 iron in the tak. , , *- ■■■; ' , -. ,. ,. . 



mena which refult from the action of water upon thiscompound, 



it becomes obvious that the fulphur is joined to the iron, detected 

 before, in the form of a fulphuret of iron. Hence it becomes 

 evident that while the fait continues in a dry ftate, the equili- 

 brium of the affinities of its constituent parts remains unaltered ; 

 The equilibrium but the moment we bring this compound in contact with water, 

 brokenby the a new arran g ement of principles takes place ; the water is de- 

 addition ofwater.com pofed, the oxide of iron is reduced to a llate of minimum 

 of oxidation, and appears under the form of a black powder 

 diffufed through the fluid, fulphuric acid is formed by the de- 

 compofition of the fulphurated hidrogen gas, and thus a fet 

 of bodies appears which did not previoufly exift in the fiate 

 wherein they prefent themfelves to our view. 

 Component parts It is evident therefore that 480 grains of this fait yielded by 



ofbit-nubin this analyfis. 



about i iron; g , . . 



3 fulphur ; z\ Black oxide or iron - 6 grains. 



muriate of lime; Sulphur - - - - - 14 



Gil common ,, . e ,. 



J,,? Muriate of lime - 



felt. 



12 

 Muriate of foda - 444 



476 

 Lofs - 4 



480 



How to deter- I have taken no notice in this analyfis of the quantity of 

 mine the fuiphu- fulphurated hidrogen gas evolved during the folution of a given 

 if required. 6611 c l uant » t >' °f !■& in a limited quantity of water, this being foreign 

 to my fubjeft. I merely remark that, if this is wanted to be af- 

 certained, it may eafily be found by introducing it into a glafs 

 tube clofed at the top, and furnifhed at the other extremity 

 with a ftopper, a weighed quantity of fait, and then adding 

 to it a meafured quantity of water, taking care to fill the tube 

 with this fluid no higher than about •§-. Having done this let 

 the tube be flopped, and agitate it till all the fait is diflblved, 

 or at leaft till no more gas is extricated. Then let the tube be 

 immerfed into warm water, and let it Hand undifturbed : re- 

 move the (topper carefully fo as to get rid of the depofited 

 oxide of iron, and introduce into-the faline folution tube, ni- 

 trous gas, in fmall quantities, till no further diminution of the 

 gas in the upper part of the tube takes place, or till no more 



/ red 



