ON MANGANESE 73 



phosphorus (Sec. vm.) ; for microcosmic salt likewise 

 produces a precipitation. 



SECTION XXVIII. 



The effects produced on manganese by the acid of 

 tartar are remarkable, on account of the effervescence. 

 Manganese does not enter with any acid into a colour- 

 less combination, without being first united with phlogiston. 

 The small portion of phlogiston which it naturally contains 

 (Sec. xv. (a), (b), (c)) may serve to render it soluble in all 

 acids ; but this only in very small quantity. The effervescence 

 which happens in the present case shows that a part of 

 the acid of tartar is entirely destroyed, in consequence of 

 the combination of its phlogistic part with the manganese, 

 as is explained in Sec. xxn., in which the destruction of 

 animal and vegetable substances is described. To this 

 it may be added, that if you make the solution with a 

 proper proportion of sugar, gum, etc., there will not remain 

 the least mark of those substances (Sec. xvi. (a)). This 

 is easily proved; for if such a solution be filtered, in- 

 spissated, and slowly calcined with concentrated vitriolic 

 acid, there should necessarily appear some blackness from 

 the burned sugar, which however does not take place. 

 During this decomposition of sugar or gum, there arises a 

 vapour that vellicates the nose; and if it be collected in 

 a receiver, it appears to be pure vinegar. From diluted 

 vitriolic acid, sugar and manganese, this acid is obtained 

 in its purest state. 



SECTION XXIX. 



Among the vegetable acids, distilled vinegar combines 

 most loosely with absorbents ; for the acids of lemon and 



