THE TROPICAL AGRlCULTURiST. [Dec. i, 1893. 
Lemon Grass Oil. 
This oil is distilled from the grass yl;ii,<//'<y/w</o» 
citratHs of De Candolle, which is cultivated on 
an extensive scale in Ceylon and .Singapore. 
The oil in also known as oil of verbena from its 
odour resembling tiiat of the sweet-scented 
verbena. Anothei- name by wliich it is known 
is Indian melissa oil. Gladstone gives the specific 
gravity of tliis oil as -89.^2 at l.')'.5C., that of the 
oil from Penang being -HTtte for the same tem- 
perature. Bentley says : " It is spoken highly of in 
" India as an external ai)i)lication in riieumatisni 
"and for internal use in cholera. It possesses 
"stimulant, carminative, antispasmodic, and dia- 
" phoretic properties. The fresh leaves are some- 
" times Used as a substitute for tea and the 
"centre of the stems for Havoring curries.'' 
Othrr Ind'tau drass Oils. 
An oil is derived from AndntpuijoK podi nudes 
known under various names, sucli as oil of gera- 
nium, oil of ginger giass, grass oil of Namur. In 
India it is known as Kusakatel or liusa r)il- It is 
said to be used to adulterate the true geranium 
oil and otto of rose. If this is tiie same as 
Dr. Gladstone refers to in the table as Indian 
geranium oil its specific gravity is •9043. 
An oil is derived from Andntpogoii mKricafus, 
which has also many names, .sucii as khus- 
khus, cuscus or vettiver or vetiver. It is from 
the roots of this tall tufteil perennial grasM 
tliat the oil is obtained. The leaves of tiie 
grass are without perfuni'^ ; but the roots are 
very fragrant. When dried the odour is ]es« 
perceptible ; but on moistening the dried roots 
the perfume is again given out. Hence it is used in 
India woven into screens, wiiich, when moistened, 
both cool and perfume the atmosphere. The 
yield of oil from the roots has lieen variously 
stated at from 2 ox. per 100 lbs. to 10 oz. per cwt. 
I have also seen it given as from -8 to 1 per 
cent of the root. The oil is said to possess 
stimulant and diaphoretic i)r()perties. The si)ecific 
gravity of this oil according to (Gladstone is 1-007. 
Oil of I'ah/iouli. 
This oil which is much used in i)erfumery 
Table of Essential 
IS dihtilled fioni the leaves of Pot/ostifiiott 
jiatehouli. The leaves of this plant are exported 
froni Singapore to Euroj>e. I am not aware that 
the leaves aie exported to any extent from 
Ceylon ; hut a small parcel sent to England 
in J887 was valued in Mincing Lane at 9d per lb,, 
the leaves arriving in a slightly mouldy 
condition. (Jood Singapore leaxes at that time 
were worth from one shilling to one shilling 
and a penny ^ler lb. 
The lea\ es are said to yield 1^' j>er cent of esi^ejice. 
The following table giviu},' a numerical ex- 
pression to certain of the physical chaiatterislics 
of essential oils is extracted from the article 
perfuniei v in "Chemistry theoretical and practical." 
The author of the article remarks ; " KsKential 
'' oils possess great refractive and dis|>eisive 
" j>ower and exhil)il peculiar effects when suli- 
" mitted to the action of a ray of polarixed 
" light — some being dextio. others laevo rotatory 
" in various degrees, while a few are ina< tive. 
" The rotatory jxtwer is given for a tube 10 inches 
" long; this length of a solution consisting f>f e<]iial 
" parts of cane sugar and water giving a rotation of 
" 10.5'". It should be remarked that the jtrfMluct 
" obtained by anj- one of the onlinary nieth<Mls »»f 
" i>reparation rarely consists of a simple volatile 
" oil, but generally is a mixture of two or 
" more oils. One of these, a hydrocarbon, 
" is lighter an>I more volatile thaii the other 
" which is either an oil containing oxygen or 
" a camphor. Hence various sampleN of crude 
"oils may show slight differences in the jiro- 
" perties here given. The hixtory of the 
"specimens used in the determinations wai- 
"generally well known, and the examination of 
" them gave no reason to doubt their genuineness, 
" the only sign of impurity being a little 
" alcohol in one or two.'" From information fur- 
isheil by Dr. Trimen I have marked with a dagger 
the j)lants ciltivated in Ceylon, principally in the 
Botanic (iardens, which yield essential oils. The 
only one in the list that is from a plant native to 
Ceylon is vetivert from cuscus grass (Andropoyon 
muriratiis.) 
Oils. ((iLAUSTONK.) 
Anise ... 
Atherosperma moschatuni 
Bay 
Berganiot 
,, Florence 
Kirch bark 
TCajeput 
J Calamus 
,, Hamburg 
Caraway 
Hamburg 1st dist. 
M „ 2nd ,, 
Cascarilla 
Cassia ... ... <.. 
Cedar ... 
tCedrat... 
Citron ... 
tCitronella 
,, Penang 
f-Cloves .. 
■f Coriander 
tCubebs 
Dill 
Source. 
Pimpinella anisum .. 
Laurus nobilis 
Citrus bergamia 
Betula alba 
Melaleuca minor 
A corns calamus 
Cariim carui 
Croton eleuteria 
Ciniiamomum cassia 
Juniperus virginiana 
Citrus medica 
Andropogon nardvis... 
[ens 
Caryophyllus aroniati 
Coriandrum sativum 
Piper cubeba 
Anethum graveolens 
Specific 
Gravity 
(al5-o°'C 
•9852 
r0425 
•8808 
•8825 
•8804 
■9005 
•9203 
•9388 
•9410 
•8845 
•9121 
•8832 
•89.-)6 
1 0297 
•9622 
•8584 
•8914 ' 
•8908 
•8847 
1 0475 
•8775 
•9414 
•8922 
Rotation ofl 
a column I 
10 inches ' 
lontr. 
Piincipal Applications. 
(From Encyc. Brit.) 
-I- 
1 ° 
7 = 
6° 
+ 23° 
+ 40 = 
+ 38° 
43° -5 
42° ? 
63° 
+ 26 = 
0° 
+ 3° 
+ 156° 
- 4° 
- 1° 
- 4° 
+ 21° 
+ 206° 
* 'J'he specitic gravity of citron, lign-aloes, pimento and vetiveit 
19°, 18°, 10°, and J9-5° respectively. 
Medicine, flavouiiDg 
do 
do perfumery, fiavouriiig 
do do do 
do do do 
Medicine 
do 
do 
Medicine, flavouring 
do do 
do do 
do do 
do perfumery, flavouring 
Perfumeiy 
do 
Perfumery 
do [ing, arts 
Medicine, perfumery, flavour- 
do flavouring " 
do 
do do 
s given tor th^ temperature 
