342 Researches respecting 



The liquor furnished by the skins, &c. when subjected to 

 the press is less coloured. 



The southern wines, and, in general, those made from grapes 

 collected in places well exposed to the south, are more coloured 

 than the wines of the north. 



Such are the practical axioms which have been sanctioned 

 by long experience. Two fundamental truths thence result : 

 the first is, that the colouring principle of wine exists in the 

 skins of the grapes ; the second is, that this principle does 

 not detach itself, and is not completely dissolved in the vint- 

 age but when the alcohol is developed in it. 



We shall treat in the proper place of this colouring prin- 

 ciple, and shall show, that though it approaches resins in 

 some of its properties, it is, however, essentially different. 



Any one, after this short exj^lanation, may account for all 

 the processes usual for obtaining wines more or less coloured ; 

 and may readily conceive that it is in the power of the agri- 

 culturist to give to his wines whatever tint of colour he 

 chooses. 



[To be continued.}. 



XL 11. Researches respecting the Laws of Affinity, By 

 C. Berthollet, Member of the French National 

 Institute, 



[Continaed from p. 153.] 

 X* Of the Determination of Elective Affinities, 



J. O determine the elective affinity of two substances for a 

 third, according to the idea which we ought to form of it, is 

 to ascertain in what ratio this third substance ought to divide 

 its action between the two former, and at what degree of 

 saturation each of them ought to be 'Wllen their forces are 

 equally opposed. The respective adfinities will be propor- 

 tional to the degree of saturation whic^i each has attained in 

 proportion to the quantity which has acted; so that, if the 

 quantities are equal, the comparative degree of saturation will 

 give the measure of the respective affinities. 



2d, When I speak of the saturation of a substance, I do 



not 



