318 COMBINATION OF MERCURY 



tual combination of mercury and the marine 

 acid. 



The relation betwixt menftrua and the bodies 

 they didblve, is eilabliihed by a conflant and 

 univerfal law of nature, in fuch a manner, that 

 they reciprocally fa titrate each other ; that is, 

 are mutually diminished in their eilicacy and a- 

 crid properties. From this combination, a ne\f 

 form of each mixt body arifes* ; whole qualities, 

 although they are generally to be attributed to 

 the character of the condiment parts, and the 

 confullon of the properties of each, yet they 

 fometimesdiirer entirely from the characlerof the 

 menftruum, and of the body diflblvcd. An ex- 

 cefs of either principle gives birth to another 

 genus of mixture, under which the true nature 

 of the combined fubltance is often concealed. 

 By taking away this excefs of the one, or fup- 

 plying the deficiency of the other principle, the 

 obfcurity is removed and the mixt body aflumcs 

 its proper character. This is commonly the cafe 

 in the union of acids with lixivial falls, earths, 

 or metals. But fuch is the peculiar nature and 

 condition of mercury combined with the marine 

 acid, that it fometimes unites with a lef*, fume- 

 times a greater proportion of acid ; and can 

 with great difficulty be forced from the mixture 

 into which it has once entered, to make part of 

 another. There are three forms under which 



