104 
ORIGINAL COMMUNICATIONS. 
The plan of arbitrary symbols to express other organic 
bodies might be still farther carried out, but has not at present 
been adopted to any extent. Some other products of organic 
matter have, however, been thus designated, of which Bz for 
benzule is a case in point. 
Some modifications in the mode of stating formulae have 
been suggested by Liebig and Poggendorf, and adopted in 
the edition of Turner's Chemistry, now in course of publi- 
cation in London, under the superintendence of Professor 
Liebig and Wilton G. Turner, brother of the deceased 
author. Instead of placing the number after the symbol at 
the top, it is brought down partly below the line, thus sul- 
phuric acid is represented by S0 3 instead of SO . This 
modification would be productive of little or no embarrass- 
ment to those who are well acquainted with the use 
of symbols, but to the learner it would be otherwise. — 
Many are deterred from attempting to obtain a knowledge 
of symbols by the apparent difficulty of the subject, and this 
would have a similar tendency by the introduction of syno- 
nymous symbols, and additional variety in the modes of 
expression, This change may prevent, in those conversant 
with mathematics, the confusion arising from the numbers be- 
ing in the same position as the indices of the powers in algebra; 
but this would hardly compensate for the difficulties which 
beginners would find in the increased variety of notation. 
Another proposition of Liebig and Poggendorf, well de- 
serving of attention, relates to the different symbols for water: 
Aq, HO, and H. They restrict the use of Aq to denote 
water of crystallization, and propose to introduce another 
symbol to express combined water, as in the hydrates, viz.: 
a small h placed after the symbol and a little below the line. 
Thus, hydrate of potassa would be represented by K h . The 
other symbols HO and H, they propose to use in doubtful 
cases, or when chemical changes are to be explained. An 
illustration may be taken from malic acid. This acid carries 
with it into combination one equivalent of water. Crystallized 
malate of magnesia consists of one equivalent of malic acid, 
