Berzelius on the Use of the Bloio-pipe. 3 21 



our readers with particular passages, since, after having care- 

 fully compared the two translations, we do not find any suffi- 

 cient reason to induce us to revoke our opinion of this nouvean 

 systeme. 



We have been guilty ourselves of an omission, in the review 

 alluded to, in having left unnoticed the signs which Berzelius 

 has invented, to express the composition of chemical com- 

 pounds and minerals; we shall therefore' devote a few words 

 to them in this place. " When we attempt," says our author, 

 " to express chemical proportions, we perceive the necessity of 

 having chemical signs." {Essai sur la Theorie des Proportions Chi- 

 7niqties, p. 109,) and accordingly he adopts two kinds, one chenii* 

 cal, the other mineralogical. With the former, 1st. a simple sub- 

 stance not metallic (which he calls a metalloid), is denoted by the 

 initial letter of its Latin name, although it may be also common 

 to the name of some metal ; 2d. a metal having the same initial 

 as another metal or a metalloid, is denoted by the two first let- 

 ters of its name, or should these be common to some other name, 

 then the first different consonant is added to the initial letter 

 instead. Thus O. =; oxigenium, S. = sulphur. Si. = silicium, 

 St. = stibium, Sn. = stannum, Sfc. A chemical sign only in- 

 dicates a single atom; to denote a greater number, a figure is 

 placed to the left of it, like an algebraical coefficient: thus Cu 

 + O, signifies protoxide of copper, and Cu + 2 O peroxide of 

 copper. But since oxygen enters into most combinations, and 

 often in the proportion of several atoms, instead of employing its 

 proper sign O, with or without its coefficient, the number of its 

 atoms is indicated by points placed over the base, each point 



denoting an atom of oxygen. Thus Cu = protoxide of copper, 



Cu = peroxide of copper, Su = sulphurous acid, and Su == sul- 

 phuric acid, i§-c. Proto-sulphate of copper is expressed by com- 

 bining these two signs, as Cu S, and the persulphate by Cu S." 

 the exponential figure, " denoting that it contains two atoms of 

 acid. The composition of a salt with more than one base is ex- 

 pressed by connecting the signs by the usual algebraic mark of 

 addition. Sulphate of potassa and alumina, for instance, is de- 

 noted by K S^ -h 2 Al S^; (K being assumed to represent ka- 

 lium, i. e., potassium,) and crystallized alum, in which these in- 

 gredients are combined with several atoms of water (expressed 



by H ' O.) is represented by (K S^ + 2 Al S'') -j- (48 H = O.) 

 (See Essai, p. 113.) The mineralogical signs are formed on a 

 similar model, but are more simple. They consist of the initials 

 of the elementary bodies in the italic character, the dots denot- 

 ing the atoms of oxygen are omitted, and water is represented 

 merely by Aq. Black Siberian Mica for instance is denoted' 



