24 
JE T H 
JE T H 
7E T I 
to pass through a red hot porcelain tube, it is 
decomposed completely, and u great quan- 
tity ot carburated hydrogen gas is obtained. 
/Ether, when exposed to a cold of — 46°, 
freezes and crystallizes. 
3. /Ether is soluble in 10 parts of water, ac- 
cording to the count de Lauraguis. 
4. W hen aether is admitted to any gaseous 
body standing over mercury, it always doubles 
the bulk of the gas, as Dr. Priestley iirst ob- 
served. If oxygen gas, thus expanded by 
sether, is presented to a lighted candle, the 
aether burns with great rapidity, but produces 
no explosion. But if one part in bulk of this 
expanded oxygen is mixed with three parts 
of pure oxygen gas, and kindled, a very" loud 
explosion takes place : the products are water 
find 2 % parts of carbonic add. Mr. Cruik- 
shank, to whom we are indebted for this in- 
structive experiment, ascertains, that one part 
of the vapour of aither takes 6.8 parts of oxy- 
gen gas to consume it completely ; and from 
the relative proportions of the two products, 
lie has shewn that the carbon which tether 
contains is to its hydrogen as 5 to 1. 
5. The action of the simple combustibles 
on tether has not been tried, if we except 
phosphorus, which it is capable of dissolving 
m small proportion. The solution is transpa- 
rent; but the addition of a little alcohol to it 
renders it milky. This furnishes us with a 
method of ascertaining whether aether is so- 
phisticated with alcohol. 
6. /Ether lias no action on metals ; but it 
revives several of the metallic oxides when 
mixed with their solutions in acids. Jt takes 
gold from its solution in nitro-muriatie acid. 
7. It is probable that it has no action on 
fixed alkalies and earths ; but it combines, or 
at least mixes readily, with ammonia. 
It absorbs nitrous gas in considerable quan- 
tity. ■ 
8. Sulphuric acid seems capable of convert- 
ing it into a peculiar kind of oil, known by the 
name of sweet oil of wine. 
If we Till a bottle, capable of holding three 
or four English pints, with oxymuriatic acid 
gas, taking care to expel the water as com- 
pletely as possible, and then throw into it about 
a dram or half a dram of good aether, cover- 
ing its mouth immediately with a piece of 
light wood or paper, in a few seconds white 
vapour will be perceived moving circularly 
in the bottle: this will lie soon followed by an 
explosion accompanied with flame ; at the 
same time a very considerable quantity of 
charcoal will be deposited, and the bottle 
will be found to contain carbonic acid gas. 
/Ether is capable of dissolving the volatile 
oils. It combines with alcohol in almost any 
proportion. 
1 be method of preparing nitrous cither, pro- 
posed by Navier, was this : twelve parts of 
alcohol are put into a strong bottle, which is 
kept surrounded with water, or rather with 
ice : eight parts of nitric acid are poured in 
at intervals, the mixture being agitated after 
every addition. The bottle is then well- 
corked, and the cork secured by leather. 
/Ether gradually forms at the surface of the 
liquid. After five or six days, when the for- 
mation is supposed to be over, the cork is to 
be pierced with a needle to allow a quantity 
of nitrous gas to escape, which would other- 
wise carry the aether along with it. The cork 
is then to he drawn ; the whole liquid is to be 
poured into a funnel, and by means of the 
finger the liquid below is allowed to run out 
while the aether is retained. 
TJiis method is somewhat hazardous ; for 
the quantity of nitrous gas evolved is so great 
as often to burst the bottle. Dr. Black sub- 
stituted in place of it a very ingenious process. 
He put into a glass phial the proper quantity 
of nitric acid ; over this was poured gently a 
stratum of water, and the alcohol was poured 
over all. Thus there were three strata of li- 
quids in the vessel : the acid lowermost, and 
the alcohol uppermost, separated from each 
other by the water. The acid and alcohol 
gradually combined with the water, and 
coming into contact acted on each other 
without violence ; and thus the aether was 
formed w ithout risk. 
Dehne has given another process for ob- 
taining nitric a'ther exceedingly tedious, but 
not attended with any risk. r l he alcohol is 
put into a tubulated retort, to which a large 
receiver is luted ; one 48th part of nitric 
acid is to be added every four hours, drop 
by drop, till it amounts to about one half of 
the weight of alcohol ; then the mixture be- 
comes hot, and aither passes over into the re- 
ceiver. After this a little more nitric acid 
is to be added every morning and evening. 
/Ether gradually forms on its surface. The 
acid is to be added till it falls down to the 
bottom of the retort in the form of green 
globules, indicating the formation of perfectly 
saturated nitrous acid. This is a proof that 
no more aether will be formed. 
Various other methods of preparing nitrous 
ether have been proposed by chemists; as the 
distillation of a mixture ot sulphuric acid, 
nitre, alcohol. See. But the process prefer- 
red by artists is that of Chaptal as corrected 
by Proust. A large retort is luted to a glass 
globular vessel furnished with a tube of safe- 
ty. From this globe a tube passes to a se- 
cond, likewise furnished with a tube of safety ; 
and to this last vessel are connected three 
Woulfe’s bottles in the usual way, which 
must be half full of alcohol. A mixture of 
32 parts of alcohol and 24 of acid, of the spe- 
cific gravity 1.3, is put into the retort. The 
heat of a chafing-dish is applied, and removed 
as soon as the effervescence begins. The 
greatest part of the other is detained by the 
alcohol in the first Woulfe’s bottle. This 
mixture is to be saturated with an alkali, and 
the other separated by distillation. 
Nitrous other, by whatever process it is 
procured, is never pure at first, holding al- 
ways in solution a considerable portion of ni- 
trous gas: hence its extraordinary volatility. 
It contains also a certain portion of nitric 
acid, and a little oil to which it owes its yellow 
colour. The nitrous gas separates sponta- 
neously when the aether is mixed with a con- 
siderable portion of water. By distilling it 
repeatedly from potass or sugar, the oil may 
be abstracted ; and when kept for some time, 
the nitric acid is decomposed, and a little 
water and oxalic acid formed, which sink to 
the bottom of the vessel. 
Nitric aether, as far as is known, agrees very 
nearly in its properties with sulphuric aether : 
it is equally fluid, light, and combustible : its 
state and odour are nearly the same, but not 
quite so pleasant, owing most probably to the 
foreign bodies, from which it cannot easily be 
completely freed. 
According to Mess. Fourcrov and Vauqulin, 
aether is composed of the same ingredients as 
alcohol, but Combined in different propor- 
tions. According to them, aether contains at 
greater proportion of hydrogen and oxygen, 
and a smaller proportion ot carbon, than al- 
cohol. 
AT I HO PS, or /Ethiops mineral, or 
Hydrargyrus cion sulphure, a preparation 
of mercury, made by rubbing in a marble or 
glass mortar, equal quantities of quicksilver 
and flowers of sulphur, till the mercury wholly 
disappears, and there remains a fine deep black 
powder, whence it has gotthename of afthiops, 
and it is much used in medicine. The name 
is changed in modern pharmacy to that of 
hydrargyrus cum sulphure. 
/Ethiops antimonialis, a combination of' 
the sulphurels of antimony and mercury ; it 
is prepared by fusing crude antimony in an 
earthen crucible, and when it is on the point 
of fixing, add to it an equal weight of hot 
mercury : the mixture at first becomes more 
fluid, and after a while solid : when cold it 
must be levigated in a mortar and washed. 
The medical effects of this preparation in 
small quantities are sudorific ; in larger doses 
it is a purgative and emetic. 
/Ethiops vegetnbilis is prepared by burn- 
ing the sea-wrack or sea-oak in the open air, 
and then reducing it into a black powder, ft 
is used to reduce scrophulous swellings, and 
in cleansing the gums and teeth. 
/ETHUSA, a genus of the pentandria di- 
gynia class and order, belonging to the natu- 
ral order of umbellate or umbeiliferax 
The calyx is an universal umbel expanding, 
the interior rays shorter by degrees; with a 
partial umbel, small and expanding. There 
is no universal involucrum ' the partial one is 
dimidiated with three or five leaflets, and 
pendulous; the proper perianthium scarcely 
discernible. The universal corolla is uniform, 
with fertile florets ; the partial one has five 
heart-inflected unequal petals. The stamina 
consist of five simple filaments, with roundish 
anthers. The pistillum is a germen beneath, 
with two reflected styli ; the stigmata obtuse. 
I here is no pericarpium ; the fruit is ovate, 
striated, and tripartite. The seeds are two, 
roundish, and striated. There is but one spe- 
cies, viz. the a-thusa synapium, fool’s parsley, 
or lesser hemlock (a native of Britain), which 
grows in corn-fields and gardens. This plant, 
from its resemblance to common parsley, has 
sometimes been mistaken for it; and when 
eaten, it occasions sickness. If the curled- 
leaved parsley only was cultivated in our gar- 
dens, no such mistakes would happen in fu- 
ture. Cows, horses, sheep, goats, and swine, 
eat it. It is noxious to geese. 
AETIANS, in church-history, a branch of 
Arians, who maintained that the Son and 
Holy Ghost are in all things dissimilar to the 
Father. 
AETIOLOGY is a figure of speech, where- 
by, in relating an event, we at the same time 
unfold the causes of it. 
/ETIT/E, or TEtites, a name given to 
pebbles or stones of any kind, which have a 
loose nucleus rattling within them, and called 
in English the eagle-stone. So far from being 
a particular genus of fossils themselves, we 
find atita: among very different genera, but 
the most valued is that formed of the several 
varieties of our common pebbles. As to the 
formation of aitite, the naturalists account for 
it from this consideration, that as the nuclei 
are coarser and more debased by earth than. 
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