926 ELEMENTS OF MATERIA MEDICA.
2. Freezing. —Olive oil is completely solidified when cooled h) ^poppy oil, however, remains in part liquid. Even two parts of o l ' ^to one of poppy oil will not completely congeal (Guibourt, Hist- des
t. ii. p. 603). Je
3. Electrical diagometer. —Olive oil, according to Rousseau (J° u ^ e{Pharm. t. ix. p. 587), conducts electricity 675 times worse than ^ ^vegetable oils. The addition of two drops of poppy or beech-nut 0 r154i grains of olive oil is sufficient to quadruple the conducting P jof the latter. To ascertain the conducting power of oil, Rousseau ^the electrical diagometer (from ciayw, to conduct ; and gerpem, to m _ ea
It consists of one of Zamboni’s dry piles and a feeblv-magnetized n ^ uCeSmoving freely on a pivot. The electricity developed by the pile P r0 jsa deviation in the direction of the needle ; but when any substan _interposed between the needle and the pile, the deviation is less m 1portion to the bad conducting power of the interposed substance. ^
4. Formation of elaidine. —If recently-made nitrate of mercurypared by dissolving 6 parts of mercury in 7*5 parts of nitric acid, S P"1*36) be mixed with twelve times its weight of pure olive oil, an ^ 0 fmixture strongly agitated, the whole mass becomes solid in the c r ° U u jgca few hours; this, however, does not occur with adulterated. ^ e *1*^of the presence and quantity of foreign oils by the degree and q lllC
of solidification of the suspected olive oil (see p. 489). fhi0-
Composition.—I n 1808, Gay-Lussac and Thenard (Reck. Phy s - .gj 5 ,ii. 320) examined the ultimate composition of this oil. con -
Braconnot (Ann. de Chim. xciii. 240) ascertained the proximatestituents of it; and subsequently Saussure (Ann. de Chim. et Phy s ■ ' ‘p. 349) examined the ultimate composition of these constituents.
Braconnot's Proximate
Ultimate Analyses.
Analysis.
Sat
Carbon.
. 76*034
.. 73
Hydrogen.
. 11*545
Margarine .
.. 28
Oxygen .
. 12*068
Nitrogen.
. o-ooo
. 0*353
Elaine 100-000
ss
mre^ aeV
1. Elaine or Oleine . —Braconnot obtained it by exposing olive oil to a temp era ^ aS a
about 21° F. in order to cause the congelation of the margarine. The elai> iegreenish yellow liquid ; at 14° F. it deposited a little margarine. abo r< ’’
2. Margarine —The solid matter of olive and other vegetable oils obtained as jis usually denominated stearine, but Lecanu (Ann. de Chim. etPhgs. Iv. 204) has P° ro0] -eout several characters by which it is distinguished from that principle: thus, U > s ff ; t bfusible, and is much more soluble in cold ether. In most other respects it agr eestearine.
Commerce— The duty on olive oil is £4. 4s. per ton, except onbroughtfrom Sicily,whichis£8. 8s. In 1839, duty was paid on 1' 2 > 37 q aS
of
Physiological Effects, (a.) On vegetables.— Olive oil, as
other fixed oils, acts injuriously on the roots of plants, by obstn^their pores and meatus, and preventing the passage of water (DecaimPhys. Veg. p. 1347). . s
(6.) On animals .—Injected into the veins, the fixed oils prove mj u ^by their mechanical operation. They obstruct the circulationcapillary vessels, and in this way cause death. Both Courten and