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LX I. Remarks on the Compounds derived from the Htearopten 
of Oil of Peppermint. By Robert Kane, M.D., 
T N my paper on the constitution of the essential oils, 1 no- 
ticed that the composition of the oil of peppermint as 
determined by my analyses approximated to that announced 
by Blanchet and Sell as belonging to the solid crystalline 
substance which often forms in it ; but at the same time I 
stated, that from the utter discordance of Blanchet’s results 
among themselves, no confidence could be placed in them. 
The formula I adopted for oil of peppermint is Cgj Og j 
and in order to establish a more direct comparison I will 
subjoin two of the analyses by which that formula was esta- 
blished. 
Experiment. Theory. 
Carbon 
I. 
78-06 
11. 
77*81 
Cai 128-9 
78*14 
Hydrogen . . 
12*32 
12*11 
Hjo 20-0 
12*12 
Oxygen ... 
9*62 
10*08 
Oa 16-0 
9*74 
100*00 
100-00 
164*9 
100*00 
The two analyses of the stearopten made by Sell and 
Blanchet, gave results which I will also subjoin. 
Experiment. 
Theory. 
Carbon 
I. 
79*63 
II. 
77*27 
Cio 
61*40 
77*28 
Hydrogen .. 
11*25 
12*96 
Hio 
10*00 
12*59 
Oxygen ... 
9*12 
9*77 
O 
8*00 
10*12 
79*40 
100*00 
The total discordance of these results, coupled with the fact, 
that on analysing the liquid oil of peppermint Blanchet and 
Sell had obtained numbers quite different from each other, 
and from the truth, shows that for purposes of further re- 
search the investigations of Blanchet and Sell cannot be taken 
as a standard. 
Mr. Walter has recently published a memoir on the cry- 
stallized essence (stearopten) of peppermint, in which he 
lays down as the basis of his very interesting researches 
Blanchet’s formula, and supposes that its truth is confirmed 
by his own analyses. With this I should not, however, have 
anything to do, had not Mr. Walter made the same obser- 
vation with me, of how close my formula for the liquid oil 
approached to Blanchet’s for the stearopten, and insinuated 
* Communicated by the Author. 
