Jellett— 
On Chemical EquiUhriiim. 
513 
All these have single heads. In Galera there is a deeper adductor 
indicis quite separate. 
first dorsal, an abductor indicis. 
Second dorsal, an abductor medii. 
Third dorsal, an adductor medii. 
Fourth dorsal, an abductor annularis. 
All of those had two heads but the second. 
There is an abductor ossis metatarsi minimi digiti in both. 
The decimals appended to the muscles are fractions of an ounce 
avoirdupois, and refer to the muscles of the Civet. 
XLV. — On the Questiotst of Chemical EQuiLiBEruM. By the Rev. J. H. 
Jellett, B. D., S. T. T. C. D., Peesident. 
[Read November 30, 1873.] 
The determination of the lavs^ according to which an acid divides 
itself between two bases which are present in the same solution has 
been long known to be one of the obscure questions of Chemistry. 
It is generally admitted by Chemists that there is a division, and that 
the relative masses of the two bases exercise an important influence 
upon the law which governs it. But the law itself is unknown. 
The object of the present paper is, to give at least a partial solution 
of this problem. 
The author proposes to treat the question as one of Chemical 
Equilibrium, defining these terms as follows : — 
Two or more substances may he said to he in chemical equilihrium if 
they can he brought into chemical presence of each other {as in a solution), 
without the formation of a7iy new compound, or change in the amount of 
any of the substances ivhich are thus brought together. 
If now an acid be added to a mixture of two bases, the result 
will in general be that four substances will be present in the so- 
lution, namely, two salts, and two portions of bases remaining 
uncombined. It is evident that these four substances are in chemi- 
cal equilibrium. The question, then, which arises is this : — What 
relation, or relations, must exist between these four substances? 
In the language of Mechanics, what is the equation (or equations) 
of equilibrium ? 
The author showed that there can be but one equation of equili- 
brium, inasmuch as the quantities of the four substances which are 
present in the solution are functions of three independent variables, 
namely, the original quantities of each base (2), and the original 
quantity of acid (1), these quantities being, within certain limits, 
arbitrary. 
