December SO, 1871.] THE PHARMACEUTICAL JOURNAL AND TRANSACTIONS. 
521 
THE APPLICATION" OF MOLECULAR 
ROTATION TO THE DETERMINATION 
OF THE VALUE OF CINCHONA BARKS. 
BY DR. J. E. DE VRIJ. 
Since the publication of my first paper on this 
subject in the Pharmaceutical Journal of July 1st, 
tlie German Chemical Society at Berlin received on 
the 19th of the same month a paper from Mr. O. 
Hesse* (of Stuttgardt), containing a condemnatory 
criticism of my paper. Since the labours of this 
chemist in the held of quinology are highly esteemed 
by me, I am happy that my paper so soon attracted 
his attention, though I regret that he could not 
spare some more time to apply my process practi¬ 
cally to some of the many barks which come into 
his hands. If he had done so, I am sure that his 
criticism would have been less condemnatory, and 
that he would probably have agreed with me that 
my process, notwithstanding all the imperfections 
which I have myself indicated in my paper, is a 
very valuable auxiliary in the investigation of cin¬ 
chona barks. But, however this may be, I have 
since continued my investigations in the same direc¬ 
tion, and have thus been led to amend my process. 
In my former paper I recommended two observa¬ 
tions to be made:— 
1. The molecular rotation of all the alkaloids. 
2. The molecular rotation of the part insoluble in 
ether. 
I have since found it necessary to add a third ob¬ 
servation, viz. to determine the molecular rotation of 
the part soluble in ether. The publication of my 
experiments in this direction will prove that of all 
the three observations, the last is the most interest¬ 
ing for the manufacturer of quinine :— 
C. Calisaya hybricla from Java (C. Hassk., Miq.)f 
Mixed alkaloids . . . [a] j = 50 o- 2 f Sc. 
Part insoluble in ether . [«]j = 102°'7r?. 
Part soluble in ether . . [a] j = 97 0f r. 
C. officinalis from Ceylon.| 
Mixed alkaloids . . 
Part soluble in ether . 
a] j = 145 C N • 
a] j = 162°^ . 
Bough mixed alkaloids from G. succirnbra. 
Darjeeling, prepared by Dr. B. Simpson. Re¬ 
ceived by me 24tli August, 1871. 
Mixed alkaloids . . . [a] j = 24°^. 
Part soluble in ether . . [«] j — SDTl’Sr. 
The mixed alkaloids proved to contain all the five 
alkaloids. 
C. succirnbra from Ootacamund. 
Bark sold in London, August, 1807. 
cmchonicline and amorphous alkaloids, whilst not a 
trace of quinine could be found. 
I will not occupy the space of this Journal by dis¬ 
cussing these results, but will only quote one fact to 
prove their importance. 
In April, 1870, the first Java bark was sold at 
Amsterdam. According to the official report to the 
Government from one of our eminent professors of 
chemistry, the Java Calisaya bark proved to be of 
first-rate quality, and not inferior to the American 
GalisayaG This judgment was founded upon the 
fact, that he obtained from that bark 3 5 per cent, of 
alkaloid soluble in ether, which he considered to be 
quinine. My investigation, however, of this bark 
proved that the part of the alkaloids soluble in ether 
turned the plane of polarization strongly to the right, 
whilst analysis proved that tills bark contained only 
a trace of quinine, but a large amount of amorphous 
alkaloid soluble in ether. 
In my former paper, I stated that the deviation 
produced by quinine is different, according as it 
is observed in solution in alcohol or in diluted acid ; 
and that I thought it very probable that this dif¬ 
ference would exist in the same direction with the 
other alkaloids. This supposition has been confirmed 
since, by the observations made by me with the 
valuable co-operation of the distinguished Professor 
of Chemistry to the Polytechnic School at Delft, Dr. 
A. C. Oudemans. We are still occupied in deter¬ 
mining the molecular rotation of all the cinchona 
alkaloids both in alcoholic and acid solutions, the 
results of which observations I intend to publish in 
this periodical as soon as they are completed. 
VESICATING INSECTS. 
BY M. C. COOKE, M.A. 
(Continued from page 504.) 
Margined 
Bltster-fly, Lytta marginata, Latr.; 
black, with the margins of the elytra 
asli-coloured.—Oliv. Ent. t. 1. f. 2 ; 
Durand, Journ. Phil. Col. of Pharm. 
ii. p. 274. f. G; Wood and Baclie, 
Disp. U. S. (18G7) p. 20G ; Harris, In¬ 
jurious .Insects (18G2), p. 137. f. G2 ; 
Packard’s Guide, f. 454. Lytta mar¬ 
ginata , Fabr. S. E. p. 260 ; Brandt 
and Rntzb. ii. t. xviii. f. 11. Meloe 
cinereus, Eorst. Nov. Sp. i. p. 62. 
Epicauta cinerea , Leconte, Cat. Col. 
Fig. 10. —Lytta U. S. 
marginata. Inhabits North America and (ac¬ 
cording to Fabricius) the Cape of 
Mixed alkaloids . . . [a]j = 12 a 8V. 
Part insoluble in ether . a .j — 29°'3 
Part soluble in ether . . [a] j = . 
The mixed alkaloids proved to contain four alkaloids 
and no quinidine. 
C. Calisaya from Java. 
Bark from a stem preserved in the Colonial 
Museum at Haarlem. 
Total amount of alkaloids 37 per cent, [a] j=115°-?. 
Part soluble in ether.[a] j=113 c W. 
The alkaloids consisted of quinidine, cinchonine, 
Good Hope. 
This is somewhat larger than C. vittata and of a 
different shape. The elytra are black, with the 
suture and margin asli-coloured. The head, thorax 
and abdomen are black, but nearly covered with an 
ash-coloured down; and on the upper part of the 
abdomen, under the wings, are two longitudinal 
lines of a bright clay colour. The insect is usually 
found in the latter part of summer, upon different 
species of Clematis, and frequents especially the 
lower branches which trail along the ground. Pro¬ 
fessor Woodliouse, of Philadelphia, first ascertained 
* Berichte der deutsclien ohemischen Gesellschaft zu Berlin. 
Yierter Jahrgang, no. 13 (August 7,1871), s. 692. 
f Pharm. Journ., July, 1871, p. 3. X Ibid- p. 2. 
Third Series, No. 79. 
* Colonial Report for 1870, delivered by the Dutch Govern¬ 
ment to the Dutch Parliament. 
