J, Maier on detecting the adulteration of essential Oils. 278 
respects. ‘These particulars will be ascertained fully by the im- 
_ tense enterprise now manifested in sinking for petroleum. 
 cananticipate differences in respect to the limited depth, little 
_ variations of thickness at intersections, irregular yield, and ori- 
gin of the carbonaceous veins. A proper knowledge of them 
_ may lead to some modification of terms in our definitions. 
87 Park Row, New York, Jan. 23, 1865. 
& 
4 Arr. XXXIII.—Detection of the adulteration of Essential Oils 
with Oil of Turpentine by the Saccharimeter ; by Dr. Juius 
Mater, Assistant in the School of Mines, Columbia Coll x. 2; 
‘Tar essential oils, especially the expensive ones, are mostl 
- tdulterated with oil of turpentine. It is often difficult to detect 
adulteration, especially when the adulterated oil gives simi- 
action on 
‘Nght or the left hand side. These optical researches have been 
_ made by Biot, Soubeiran, Capitaine, Gladstone and Berthelot, in 
: order to establish the constitution of the camphenes. I made 
_ ‘Se researches to detect the adulteration of the essential oil 
With the oil of turpentine. 
For that purpose, a chemically pure oil of lemon which I had 
Prepared myself, was tested in a saccharimeter, the tube of which 
Was 200mm long. 
. deviation was +137°-296 for the middle yellowray. The 
‘ a a turpentine, used for the research, prepared by myself, had 
‘ A reeitic gravity of 0°865 and gave a deviation of —78°-135. 
a ys ixture of equal volumes of both these oils showed a devia- 
: : tof MOU" OS. The Galcalation gives a deviation of +32°-081 
| following manner: 
$ vol. oil of lemon = + 68°648 
$ vol. oil of turpentine = — 36°567 
1 vol. mixture = +32°-081 
‘ . A mixture of 2 vol. oil of lemon with one vol. oil of turpen- 
ies a deviation of +65°-84; from the calculation results a 
“Yiation of +67°152, as follows: ; 
$ vol. oil of lemon =-+91%531 
$ Vol. oil of turpentine = — 24°:379 
1 vol. mixture = +67°152 
