SULPHO-CARBOLATES. - 309 



have been taken from Dr. Sansorn's paper, before 

 referred to. 



Sulpho- Carbolic Acid (Syn. Sulpho-phenic orPhenyl- 

 Sulphuric Acid, C 6 H 6 SO 4 or C 6 H 5 SO 4 H) is the com- 

 pound acid resulting from the union, in equivalent pro- 

 portions, of hydrated sulphuric acid and pure carbolic 

 acid. Heat is evolved in the combination, the tempe- 

 rature being raised to 200 F., and the immediate result 

 is a syrupy fluid which slowly deposits crystals. By 

 slow crystallisation at low temperatures the pure 

 sulpho- carbolic acid may be obtained in long, slender, 

 colourless needles, which readily deliquesce in the 

 atmosphere. It may also be obtained by exactly de- 

 composing the barium sulpho-carbolate with sulphuric 

 acid, filtering from the insoluble barium sulphate, and 

 evaporating in vacuo. 



Sulpho-carbolic acid has a sp. gr. of i'288 ; its 

 odour resembles that of carbolic acid, but is less 

 intense ; heated to 400 F., it becomes of a bright red 

 colour, and when cooled, is nearly solid ; it boils at 

 540 F., and at 560 is decomposed into a black 

 amorphous inodorous mass. Nitric acid added to 

 sulpho-carbolic causes immediate decomposition with 

 violence. 



Sulpho-carbolic acid is soluble in water, alcohol, 

 and ether, in any proportions. Its solution reddens 

 litmus, and gives, like the aqueous solution of car- 

 bolic acid, a beautiful mauve or purple colour, on the 

 addition of a solution of per-salt of iron. The 



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