44 
SELECTED ARTICLES. 
It may also be mentioned that tartaric acid, when added to 
a portion of the solution, will throw down the potash in the 
form of a difficultly soluble salt, (the bitartrate of potassa, or 
cream of tartar,) but the soda will be retained in solution, and 
may be separated by subsequent evaporation. 
Difficult as are these methods of separating the salts of soda 
and potash, and desirable as it would be to devise a more sim- 
ple one, if it is really an object to maintain a system of inspec- 
tion worthy of the name, heavy penalties should be affixed to 
the use of all adulterants, and complete analyses of the various 
samples in market should be made at short intervals by the 
inspector, or by some competent person under his direction. 
^mer. Journ. Sci. and Arts. 
ART. VIII.—ON THE RESINS. By Henry Rose. 
Researches on isomeric organic substances, and on the 
manner in which they comport themselves with other bodies 
are of the highest importance; and those of MM. Blanchet 
and Sell, on the essential oils, are among the most interesting 
of these investigations. These chemists have shown that 
many of the non-oxigenated essential oils were constituted 
alike, and the observations of other experimenters have aug- 
mented the number of isomeric bodies of this class; thus 
MM. Blanchet and Sell considered as isomeric: 1 and 2, the 
two oils composing oil of turpentine, to which they have 
given the names of dadyl and peucyl; 3 and 4, the two oils 
constituting oil of lemons, which they have called citronyl 
and cytryl; and according to M. Blanchet, to these must be 
addded, 5, oil of copaiba; 6 and 7, the two oils composing oil 
of Juniper. M. Ettling has also found that the following be- 
longed to the same category; 8, oil of cloves, and 9, oil of va- 
lerian, when they are freed from the acid with which they 
are combined. 
