OPTICAL ROTATION OF SPIRITS OF TURPENTINE.
863
yellow precipitate was secured, the reaction was stopped and the mixture poured into a large quantity of cold water, when the fluorescein separates out in a bright yellow, flocculent mass; if a dark precipitate is obtained, the mixture has been heated too long. The fluorescein may then be purified by fractional precipitation from a n alkaline solution with acid, which gradually removes a tarry impurity probably containing resacetein. Another method of purification consists in dissolving the crude fluorescein in concentrated sulphuric acid diluted with a n equal volume of water and precipitating after filtration by neutralization with sodium hydroxide. That acetic acid is actually given off in the reaction was shown by the odor, by the ferric chloride and the ethyl acetate tests. That the compound formed was actually fluorescei'n was shown by conversion into the diacetate, the dichloride and eosine. The diacetate made either by heating with acetic anhydride or by acetylation with acetyl chloride and pyridine in glacial acetic acid, after purification by crystallization from acetone, melted a t 201O, while Baeyer' gives 200'. Calculated for C,H,,O,: C, 69.23;H,3.88. Found:
C, 69.04,69.24;H, 4.03,4.09.
From this diacetate fluorescei'n was obtained by saponification. The dichloride was made by heating with phosphorus pentachloride at 180'. After crystallization from alcohol it gave a melting-point of 249' (Baeyer, 252O). Calculated for C,H,,O,CI,: C1, 19.22;Found, 19.20. Eosine was made by adding bromine t o a n alcoholic solution of the fluorescei'n. Calculated for C,,H,O,Br: Br, 49.36 ; Found, 48.76. Succinyl fluorescein was formed with elimination of acetic acid when the condensation was carried on with succinic acid instead of phthalic anhydride.
THE OPTICAL ROTATION OF SPIRITS OF TURPENTINE. BY CXAS. K. HERTY. Received Icebruary IO, 1908.
Among the physical properties of spirits of turpentine, none has proved of more interest than its optical rotation. In most specimens this property is very marked, and as the liquid is colorless and the determination readily made, many data are found on this subject in chemical literature. Slight variations in the rotation of different samples are t o be expected, a s spirits of turpentine is not a chemical compound but a mixture of substances, chiefly terpenes. From the results of numerous observations upon commercial samples, the view commonly held previous t o 1891 was that French spirits of turpentine, distilled from the oleoresin of Pinus maritima, is levo-rotatory and t h a t American spirits of turpenAnn., 183,
I.
864
CH..\S.
H. l ? E R T I .
tine, distilled in years past, alnio5.t wholly froin Pinus p a l i ~ s t rbi, is dextrorotatory. The difference in the character of the rotation was ascribed, therefore, t o the different species from which the spirits of turpentine was produced. Recognizing the fact that American spirits of turpentine is distilled from more than one species of pine, J. H. Long,' in 1891, undertook a study of the volatile oils distilled from oleoresins of well identified individual trees, these trees embracing the several species of pines subjected to turpentining in our southern states. He found that specimens from Pznus palustrzs (Long Leaf Pine )gave dextro-rotatory oils, while those from Pznus heterofihylla (Cuban or Slash Pine) gave levo-rotatory oils. Since the oleoresins from these two species are indiscriminately niiwd, at the time of collection in the woods, the rotation of the oil distilled from such a mixture would naturallv van-. Pinus paLzLstviA is the predominating species and Long attributed to this fact the dextro-rotatory character of Anierican spirits of turpentine. This T-iew has been generally accepted. The fact that spirits of turpentine is frequently adulterated with optically inactive mineral oil, led -1. NcGill' to make a large number of determinations of the rotation of conimercial samples of spirits of turpentine, in the hope of utilizing this propcrt!- for the detection of adultcration. From the widely varying results obtained he I V ~ Zcompelled t o declare the method useless. 11- evidence upon this point has been obtained from investigations carried on in this laboratory in collaboration with the U. S. Forcst Ser\+x, the experimental work hal-ing b e t n carried out b\ llessrs. George -4. Johnston and IT. S. Dickson under the direction of the writer. In order to gain a better knowledge of the oleoresins from the two principal species of pine utilized in t h e turpentine industry a t the present time, fourteen trees were selected on a Florida turpentine farin. (he-half of these were Pznws palustris, the other half Ptizzts hcterophylla. Three trees of each spccies were tapped for the first time a t the beginning of the experiments. In each case a small ?oung pine, a medium pine, and a large,old pine were selected. In another set four trees were selected, two each Pznus fialustrir and Piwus heleioph3lla. These trees had been subjected t o turpentining during the previous year, the chipping, or weekl! scarification, 011 all of t h e m having been unusually shallow, onl~7 about one-half a s drep as i5 commonly practiced. In a third set four trees were selected, two each of Pinm fiolustyis and P i x u s Iwterofihylla, which had been turpentined during the previous year and on each of these the depth of the chipping was the normal cut. The trc'cs in each set were chipped a t intervals of s e ~ w icILi\i. J . Anal. Appl. Clzem., 6 , I . Bulletin .Vo. 79, I d a n d Rez'enue Dept , CaiiaJa
S65
OPTIC.\L ROTATIOX O F SPIRITS OF TURPESTIXE.
Special precautions were taken in the collection of the oleoresins. '1'11~. cup and gutter system described in Bztlletirz ,Vo. 40, U . S. Burczz o j F L ~ I . . estry. was used. Instead of the clay cup commonly used, oxsttar pails were substituted. The entire apparatus was cos-ered with 1)lacl; oilcloth fastened securely into the bark of the tree aljox-e the chipping surface, thereby protecting the resin from light and a\-oiding thc fillitix ot the pails with rain water. Eyer>- four weeks these pails \ r e r e rtmoixd from the tree, tightly stoppered and immediatel- shipped to this laboratory for examination. The specimens so obtained were c-st,rernely piirc. a i d free froiii chips. *After removal of the pails. the Iiietn! gutters w r c ' raised t o a point near the chipping surface in order to iniiiiiiiize the aiiiouiit of oleoresin which might stick t o t h e esposc-cl lmrtioii u i the t r u n k :i.box-e the gutters. 'rhe distillation oi thc oleoresin was carried out 111 ;i ~i(Jir L X ~ . Imall boiler was first 11" .ti through :t small iron p i p in ~,\-Iiichir LYJUI(! 1 I t ' superheated then o the distillatioil ilasl; through :i glass ttille !l:i\%ig on its end a 11~11) containing a nuiii!x.r u i ol)cnin strong agitation of thc Iiloltcii oleoresin \\-:IS obtait 11-ere placed both inside the flask and in tlir oi!-lnt!i of steam and spirits of turpentine n-ere passid thr deiising bulb t o prt\Tel1t thc carr!.ing o1-t-r of solid p deilsecl in ai1 ordinary Lichig conclenser a n d Lwllcctc-cl i l ; :: 5 ~ p i i r ~ i t c 1 7 j funiicl. .After drawing off the l o w r la>.er oi w t v r . thc spirits oi tLll-I)vlitint. was transferred to a dr?- flask and allonttl t o stand o l - v r night \rith calcium chloride. Thc determinations of the optical rotation of t hc. v r i h tile oils were inade with a Schmidt and Haensch half-shatiow polariscupt , sodium flame, a t 20". In the following table are given tht. result. ironi the first collection of the oleoresin in earl>-spring: TABLEI % :
I
Tree designation.
Dianieter (inches)
Species.
P.heterophylla . . . f.palustrl's.. . . .
,
7 .o 11 5 24 5
.
1st vear, normal depth
-, ~, .
.
' I
15.0 21
P.heterofihylla . .
Uprlcal lVlllil011 IOO inni.. tribe.
Character of chipping.
. ..
.o
12. j
2nd year, shallon
$ 2
P. pa?ustri.r. . .
,
13 C) i -
P . heieropltyllu .
t,
i'
i j
5
. 13 o 110
2nd year.
normal depth
20- i'.
866
CHAS. H. HERTT.
These results show a wide variation in the optical rotation of the volatile oils from the individual trees, even among trees of the same species. I n a general way the figures give support t o Long’s view, namely that the volatile oils from the I’i)zz~.c i d u s f r i s are dextro-rotatory and those from Piazu hefero~hylltile\.o-rotator>-. That this is not strictly true, however, is evidenced by thc dextro-rotation of (P. Izcferothe lcx-o-rotation of C3 (1’. jhzlu,st?i~\). Phjdla) and more especially \$‘ith these variations iii t h e first collection from t h c several trws, the question naturally arose, \yould the variations chazige as the season ad\-anced or would the figures prow constant for t h e individual trees? The rotations for the succc.ssi\-c.collections iolloir in Table TI : ,%
I.IBLE II.--OPTIC.\L ROTATIOX IN ~ o o xlf.
I..
+ O ” I j’
2 . .
-0 330‘
3.
’
t 0 C I
-1015’
j..
-20
I
.
Collection. I..
Li;O43’ i19030’ 1S046‘
+
5‘
- 19024’
- 13’16’
-3030‘ --j
”
+ ISOIX’
j’
4.’ 6.
’.+ j’ C?.
-7’26’
1. 140i;’
11 I
c4
-, ,
- 0 ,J
~
-6’42’
f7 0 2 0 ‘
,
.
-4’d
4.
’
-4O29’
.. ... . . . . . . . . .,,.. .
2 . . 3
5.. 6., I ”
’ri.~~:, 2(i0 C. .if>.
A?.
Collection.
--,3 O j j ’ -A0 5‘ -60 6’
’
D3.
+Io3;;o’
+ I I 023’ A I 3 0 7’ - I 2 “461
-1SOjS’ - 1 i O
5 ‘20’
-1
jO 0’
4 0 3 8‘ 7’ --I 4”19’
f I ; O
0’
--I
-130
0’
-1qc
+ IOO4S’
0’
-1
XoTr.-The yield of oleoresin from C, was so small, niter the first and second collections, t h a t not enough volatile oil ci~uldbe ohtnined on distillation to fill the I O O miii. tube.
I:rom this table it is seen t h a t the rotation in most cases is quite constant throughout the year. The most marked exception is Xz ( P . heterofilz~d1u). I t is evident that some distinct change in the biological activity of this tree has taken place. for while the rotation is reasonably constant during the first half of the year, a steady increase in the lei-0character of the oil is apparcnt during the last half. In the case of C I (likewise P. Iteteyofihylla) somewhat thr reverse has taken place. -4 rather marked decrease in the levo-rotation is shown just a t the middle of the year, then the rotation remains practically constant during the last half. In the case of C3, another type of change is represented, the levo-rotation decreasing up to the middle of the season and again increasing during the latter half. Urith the limited facts a t hand, it is impossible t o interpret the signifi-
METHOD OF ANALYZING SHELLAC.
86 7
cance of these changes. That tree which shows the most marked variation, A2, is a healthy, vigorous tree, from which variations would be least expected. Nor can an explanation be offered for the wide variations in the optical rotation of oils from the Same species. All SI the trees in Series A are located within 20 yards of each other and have, therefore, the Same general conditions of climate, light and soil. Fractionation of the volatile oils from these show practically the same rise in boiling-point for the same volume of distillate. It would seem, therefore, that these volatile oils, consisting so largely of pinene, are mixtures principally of dextro- and levo-pinene,, the preponderancr of the one or the other determining the optical rotation. UNIVERSITY OF NORTHC A R O L I N A CHAPEL HILL, N. C., F e b r u a r y z , 1906.
A METHOD OF ANALYZING 8HELLAC.I BY PARKER C. MCILEINBY.
Received March 13, 1go8.
The method of analysis which is in most common use at the present time, both in England and in the U. S., for the determination of the amount of rosin in shellac, is an indirect method dipending upon the different powers of a shellac and of rosin to absorb iodine from a suitable solution. Different operators prefer different methods of making this test, some preferring fo use the old Hub1 method, and others the more modern Wijs method, as modified by Langmuir. Either of these methods is capable of giving reasonably satisfactory results, although the Langmuir method is certainly much to be preferred, both on the score of accuracy and of speed, Another method which is in use is that proposed by Parry, depending upon the solubility of the resinate of silver made irom cornnion rosin, in ether, while the corresponding resinates from shellac are insoluble. This method labors under several disadvantages r x sources of error, of which the two principal ones are the solubility of the unsaponified portion of the shellac in ether, and the danger of a decomposition of the resinate of silver before it can be separated and determined. A direct method of separating shellac and rosin and recovering the '%in, a t least, in a substantially unchanged form, is greatly to be des i r e ~ and ~ several experimenters have attempted to make such a separation by taking advantage of the solubility of rosin in petroleum &he-r, a solvent in which shellac is insoluble. No method of extr&cting fvom even a finely pulverized sample of shellac the portion solulale in rdetroleum c'ther seems to be capable of removing more than a -ll.prt of the ro$in contained in the sample. Riead before the New York Section on March 6 , 1908.
