490 THE CHEMISTKY OF ESSENTIAL OILS
Geranium oil differs to a certain extent in character according to the
locality in which it has been produced, and the difference in odour value
is even more marked than the differences in physical characters. The
principal types of oil have the following characters:—
Bourbon Geranium Oil.
Specific gravity 0-888 to 0-8965
Optical rotation - 8° „ - 14°
Refractive index 1-4620 „ 1-4677
Acid value1*5,, 1-5 „ 10
Ester „,,50 to 78 (rarely below 55)
„ „ (after acetylation) ... 205 to 230
Algerian Geranium Oil.
Specific gravity
Optical rotation
Refractive index
Acid value
Ester „
,, „ (after acetylation)
0-892 to 0-904
- 7° to - 11° 30'
1-4650 to 1-4720
1-5 „ 10
40 to 70 (rarely as low as 36)
200 to 230
French Geranium Oil.
Specific gravity
Optical rotation
Acid value
Ester ,
(after acetylation)
0-896 to 0-905
- 7° 30' to - 11°
5 to 10 i
50 to 68 (rarely as low as 46)j
210 to 230
Spanish Geranium Oil.
Specific gravity
Optical rotation
Acid value
Ester „ ...
,, „ (after acetylation)
0-896 to 0-906
- 7° 30' to - 11°
2 to 10
60 „ 100
205 „ 235
Corsican Geranium Oil.
Specific gravity
Optical rotation
Acid value
Ester „
0-896 to 0-901
- 8° „ - 11°
3-5 „ 5
56 „ 63
Sicilian Geranium Oil.
Specific gravity.
Optical rotation.
Ester value.
,, „ (after acetylation)
0-894=
- 11°
84
218
According to Puran Singh l the geranium plant growing wild in the
Nilghiris is Pelargonium graveolens. An experimental distillation of 500
1
Indian Forest Records, vol. v., pt. viii.