40 A. RK; PENFOLD. 
and also produces evidence of its identity with /\,-Men- 
thenone-3. 
The author during an investigation of the oxidation 
products of piperitone from the essential oil of Hucalyptus 
dives by means of potassium permanganate succeeded in 
isolating and identifying the following acids, viz:— 
o-hydroxy-o-methyl-4-isopropyl adipic acid. Melting 
point 143°5° C. 
«-isopropyl-y-acetyl-butyric acid. Boiling point 175 —- 
177 ©. at 12)mm: . | 
a-isopropyl glutaric acid. Melting point 94—95° O. 
This result is in entire agreement with Messrs. Schimmel 
& Co’s work on /\,-Menthenone-3 isolated from Japanese 
Peppermint Oil. 
In this connection, Simonsen’ considers that the oxime 
of M.Pt.110- 111° ©. prepared by Messrs. Read and Smith 
had probably not been entirely freed from the more fusible 
isomeride, and considers its correct melting point to be 
117-—118° C. This worker also gives the melting point of 
the «-semicarbazone as 225—227° ©. This statement 
induced the writer to review his note book dealing with 
the initial work on leevorotatory piperitone from the oil of 
EB. dives carried out between May and July 1919, and therein 
the melting point of the oxime is given as 117 = 118°, and 
the v-semicarbazone as 225— 226° C., thus confirming the 
results of Simonsen. The piperitone used had Lt ]p 20°. —D4C. 
The author had also been successful in preparing the three 
semicarbazones, viz:— 
dl-o-semicarbazone M.Pt. 225 — 226° C. 
dl-2-semicarbazone 175-—176° C. 
racemic ditto 188—189° C. 
also in agreement with Simonsen’s results. 

* Semi-Annual Report, October 1910, pages 97 — 105. 
2 J.C.S., October 1921, page 1644. 

