74 ESSAY V. 



tamarinds expel it from its union with fixed alkali 

 in acetated vegetable alkali (terra foliata tartari). Its 

 inflammable part is more closely united than in the rest 

 of the vegetable acids, since it arises with it into the 

 receiver, which is not the case with the other acids, which 

 are destroyed, except the volatile dry acids of benzoin 

 and amber. Hence it appears that vinegar acts upon 

 manganese in no other manner than diluted nitrous and 

 vitriolic acid do (Sees, xv.-xxi.). If this acid had a greater 

 attraction for phlogisticated manganese, or if its phlogiston 

 was not so closely combined, the manganese would decom- 

 pose it, as really happens with phlogisticated vitriolic acid, 

 with volatile nitrous acid, and the acids of tartar and 

 lemon. 



SECTION XXX. 



The acid of lemon is likewise decomposed by manganese, 

 as well as that of amber. During putrefaction and com- 

 bustion the acid of lemon also yields a great deal of aerial 

 acid, which is here the real cause of the effervescence 

 during the solution. The brown colour assumed at first 

 by the solution is a proof that the acid of lemon can 

 dissolve the manganese without its being first united with 

 phlogiston. The acid of tartar produces likewise in the 

 beginning a solution of a somewhat brown colour. The 

 cause of this colour is the very same with that assigned 

 with respect to the muriatic acid. 



SECTION XXXI. 



The twelfth paragraph shows that aerial acid too has 

 some effect upon manganese. I have related this ex- 

 periment to show that, from a solution in any acid, if there 



