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Officers, staff, are such as, in the king’s 
presence, bear a white stall or wand ; and 
at other times, on their going abroad, have 
it carried before them by a footman bare- 
headed ; such are the lord steward, lord 
chamberlain, lord treasurer, &c. 
The white staff is taken for a commission, 
and at the king’s death each of these officers 
breaks his staff over the hearse made for the 
king’s body, arid by this means lays down his 
commission, and discharges all his inferior 
officers. 
Officers, subaltern, are all who admi- 
nister justice in the name of subjects; as 
those who act under the earl marshal, ad- 
miral, &c. In the army, the subaltern of- 
ficers are the lieutenants, cornets, ensigns, 
Serjeants, and corporals. 
OFFICIAL, in the canon law, an ecclesi- 
astical judge, apointed by a bishop, chapter, 
abbot, &c. with charge of the spiritual juris- 
diction of the diocese. Of these there are 
two kinds; the one is in a manner the vicar- 
general of the diocese, and is called by the 
canonists officialis principalis, and in our 
statute-law, the bishop’s chancellor. There 
is no appeal from his court to the bishop, his 
being esteemed the bishop’s court. The 
other called officialis foraneus, and is appointed 
bv the bishop when the diocese is very 
large; he has but a limited jurisdiction, and 
has a certain extent of territory assigned him, 
wherein he resides. 
OFFING, or Offin, in the sea-language, 
that part of the sea a good distance from 
shore, where there is deep water, and no 
need of a pilot to conduct the ship; thus, if 
a ship from shore is seen sailing out to sea-* 
waul, they say, she stands for the offing ; and 
if a ship, having the shore near her, has an- 
other a good way without her, or towards the 
sea, they say, that ship is in the offing. 
OIL, which is of such extensive utility in 
the arts, was known at a very remote period. 
It is mentioned in- Genesis, and during the 
time of Abraham was even used in lamps. 
The olive was very early cultivated, and oil 
extracted from it in Egypt. Gecrops brought 
it from Sais, a town in Lower Egypt, where 
it had been cultivated from tjme immemorial, 
and taught the Athenians to extract oil from 
it. In this manner the use of oil became 
known in Europe. But the Greeks seem to 
have been ignorant of the method of procur- 
ing light by means of lamps till after the siege 
oTl'rov ; at least Homer never mentions 
them, and constantly describes his heroes as 
lighted by torches of wood. There are two 
classes of oils exceedingly different from each 
other ; namely, fixed oils and volatile oils. 
Fixed oils are distinguished by the follow- 
ing characters: 
1 . Liquid, or easily becoming so when ex- 
posed to a gentle heat". 2. An unctuous feel. 
3 . Ve y combustible. 4. A mild taste. 
5 . Boiling point not under 600°. 6 . Insoluble 
in water" and alcohol. 7. Leave a greasy 
stain upon paper. 
Those oils which are called also tat or ex- 
pressed nils, are numerous; and are obtained, 
partly from animals and partly from vege- 
tables, by simple expression. As instances 
mux be mentioned, whale-oil or train-oil ob- 
ta-ned from the blubber of the whale; olive- 
oil. obtained from the fruit of the olive ; lin- 
seed-oil and almoud-oil, obtained from lin- 
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seed and almond-kernels. Fixed oils may 
also be extracted from poppy-seeds, hemp- 
seeds, beech-mast, and many other vegetable 
substances. 
It deserves attention, that the only part of 
vegetables in which fixed oils are found is the 
seeds of bicotyledinous plants. In animals 
they are most usually deposited in the liver, 
though they are found also iu the eggs of 
fowls. 
All these oils differ from each other in se- 
veral particulars, but they also possess many 
particulars in common. Whether the oily 
principle in all the fixed oils is the same, and 
whether they owe their differences to acci- 
dental ingredients, is not yet completely as- 
certained, as no proper analysis has hitherto 
been made ; but it is not improbable, as all 
the oils hitherto tried have been found to 
yield the same products. In the present 
state of our knowledge, it would be useless to 
give a particular description of all the fixed 
oils, as even the differences between them 
have not been accurately ascertained. 
Fixed oils are considered at present as 
composed of hydrogen and carbon. La- 
voisier analysed olive-oil by burning a given 
portion of it in oxygen gas, by means of a 
particular apparatus. During the combustion 
there was consumed 
Of oil - 15.79 grains troy 
Of oxygen gas 50. 86 
Total 66.65 
The products were carbonic acid and 
water. The carbonic acid obtained amount- 
ed to 44.50 grains ; the weight of the water 
could not be accurately ascertained ; but as 
the whole of the substances consumed were 
converted into carbonic acid gas and water, 
it is evident, that if the weight of the carbonic 
acid is subtracted from the weight of these 
substances, there must remain precisely the 
weight of the water. Mr. Lavoisier accord- 
ingly concluded, by calculation, that the 
weight of the water was 22. 15 grains. Now 
the quantity of oxygen in 44.50 grains of 
carbonic acid gas is 32.04 grains, and the 
oxygen in 22.15 grains of water is 18.82 
grains ; both of which taken together amount 
to 50.86 grains, precisely the weight of the 
oxygen gas employed. 
The quantity of charcoal iu 44.50 grains 
of carbonic acid gas is 12.47 grains ; and the 
quantity of hydrogen in 22.15 grains of water 
is 3.32 grains; both of which, when taken 
together, amount to 15.79 grains, which is 
the weight of the oil consumed. 
It follows, therefore, from this analysis, that 
15.79 grains of olive oil are composed of 
12.47 carbon 
3.32 hydrogen. 
Olive-oil therefore is composed of about 
79 carbon 
21 hydrogen 
100 . 
This however can only be considered as a 
very imperfect approximation towards the 
truth. 
Fixed oil is usually a liquid with a certain 
degree of viscidity, adhering to the sides of 
the glass vessels in which it is contained, and 
forming streaks. It is never perfectly trans- 
parent, having always a certain degree of 
colour ; most usually it is yellowish or green- 
l 
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tsh. Its taste is sweet, or nearly insipid. 
When fresh, it has little or no smell. Its 
specific gravity varies from 0.9403 (the spe- 
cific gravity of linseed-oil) to 0.9 153 (the spe- 
cific gravity of olive-oil). 
Fixed oil is insoluble in water. When the 
two liquids are agitated together, the water 
loses its transparency, and acquires the white 
colour and consistency of milk. This mix- 
ture is known by the name of emulsion. 
When allowed to remain at rest, the oil soon 
separates, and swims upon the surface of the 
water. 
Fixed oil does not evaporate till it is heat- 
ed to about 600°. At that temperature it 
boils, and may be distilled over ; but it is 
always somewhat altered by the process. 
Some water and sebacic acid seem to be 
formed, a little charcoal remains in the re- 
tort, and the oil obtained is lighter, more 
tluid, and has a stronger taste, than before. 
Oil thus distilled was formerly distinguished 
by the name of philosophical oil. 
Fixed oil, when in the state of vapour, 
takes fire on the approach of an ignited body, 
and burns with a yellowish-white flame, it 
is upon this principle that candles and lamps 
burn. The tallow or oil is first converted 
into the state of vapour in the wick ; it then 
takes fire, and supplies a sufficient quantity 
of heat to convert more oil into vapour; and 
this process goes on while any oil remains. 
The wick is' necessary to present a suffici- 
ently small quantity of oil at once for the heat 
to act upon. If the heat was sufficiently 
great to keep the whole oil at the tempera- 
ture of 600 °, no wick would be necessary, as 
is obvious from oil catching fire spontaneous- 
ly when it has been raised to that tempera- 
ture. 
When exposed to the action of cold, fixed 
oils lose their fluidity, and are converted 
into ice ; but this change varies exceedingly 
in different oils. 
When fixed oils are exposed to the open 
air or to oxygen gas, they undergo different 
changes according to the nature of the oil : 
1 . Some of them dry altogether, without 
losing their transparency, when thin layers 
of them are exposed to the atmosphere. 
These are distinguished by the name of dry- 
ing oils, aud are employed by painters. Lin- 
seed-oil, nut-oil, poppy-oil, and hempseed- 
oil, possess this property; but linseed-oil is 
almost the only one of these liquids employ- 
ed in this country as a drying oil. The cause 
of this peculiarity has not been completely 
investigated; but it is well known that these 
oils possess the drying quality at first but im- 
perfectly. Before they can be employed by 
painters, they must be boiled with a little 
litharge. During this operation the litharge 
is partly reduced to the metallic state. Hence 
it has been conjectured t hat drying oils owe 
their peculiar properties to the action of 
oxygen ; which is supposed either to consti- 
tute one of their component parts, or to con- 
vert them into drying oils by diminishing 
their hydrogen. 
2 . Other tixed oils, when exposed to the 
atmosphere, gradually become thick, opaque, 
and white, and assume an appearance very 
much resembling wax or tallow. These have 
been distinguished by the term fat oils. 
Olive-oil, oil of sweet almonds, of rape-seed, 
and of ben, belong to this class. 
When oil is poured upon water, so as to 
