422 Mr. Srnee 07i the Galvanic Properties of the 
play half equivalents of chlorine and hydrogen, indicating 
that the substances analysed were not yet definitely charac- 
terized. 
The peculiar acid body formed by treating the essence with 
nitric acid has its origin in decompositions so complex, that, 
until its atomic weight and composition shall have been ac- 
curately determined by the analysis of its salts, it is totally 
useless to discuss it in relation to the present question. But 
here as in the other instances Mr. Walter has got too much 
carbon, although not too little hydrogen, and the additional 
quantity of carbon given by my number makes his analytical 
results more consonant to the theory. I do not wish, how- 
ever, to be considered as applying the formula Og to 
explain the origin of this body, wTich indeed I consider to 
belong to a totally different series. 
In concluding, I must observe that I admire very much the 
general exactness of Mr. Walter’s results, and the skill which 
he has displayed in this and other difficult investigations, by 
which he has been so highly distinguished. In fact, it is 
greatly to his credit that his analyses were so good, although 
he had been beguiled by the authority of Blanchet to adopt 
an insecure basis at his outset ; and I have written these re- 
marks not to diminish Mr. Walter’s merit, wffiich none can 
be more ready to express the highest sense of, but to show 
that all Mr. Walter’s investigations have but confirmed my 
former results, and that they have fully proved, that the li- 
quid and the solid oil of peppermint have the same constitu- 
tion, and that although I had not confirmed my formula by 
the accessory methods generally employed, the confirma- 
tions have come unconsciously from Mr.Walter’s hands, and 
that the formula Cgj Hgo Og is that which alone accounts for 
his interesting results. 
LX II. On the Galvanic Properties of the Plemeyitary Bo-- 
dies^ and on the Amalgamation of Zinc, By Alfred Smee, 
Esq. 
[In continuation of a former paper, p. 315.] 
I '’HE first non-metallic element we have to examine is car- 
bon. 
When a diamond is placed in contact with amalgamated 
zinc in dilute sulphuric acid, no gas is given ofi^ nor copper 
precipitated on it from a solution of that metal when touched 
by zinc. Gas coke, however, recently ignited, or plumbago, 
placed under similar circumstances, copiously evolves hydro- 
gen from its surface. The same circumstance is noticed with 
the various forms of porous coke and boxwood charcoal, but 
