C H E M 
ment they were in contaiff, there appeared in the re¬ 
ceiver a vapour as red as the moft concentrated nitrous 
acid could exhale. If a lighted taper be plunged into 
this gas, a flame is produced ilmilar to the combuftion 
of nitric ether. He concluded, therefore, that tins gas, 
when leparated, always carried with it a certain quantity 
of nitric ether; and that its fpontaneous difengagement 
is always much flower than when aflifted by water. He 
attributes the prefence of nitrous gas to the extreme fa¬ 
cility with which the nitric acid is decontpofed ; and he 
does not regard it as efl'ential to the conftitution or for¬ 
mation of nitric ether, fince, when deprived of it, this 
ether is preferved like other ethers, without breaking the 
vefiels which contain it. 
This ether has often a yellow colour. Deyeux en¬ 
deavoured to feparate this; and he perfeftly fucceeded 
by the following procefs : Diftil four parts of nitric ether 
upon one part of fugar in powder; the operation goes 
on quietly, with hardly any difengagement of air; the 
liquor obtained is very aromatic, and much lefs coloured. 
A fecond diftillation overfrefh fugar whitens it ftill more; 
but the nitric ether is decontpofed at each operation. The 
heat of boiling water is fufticient; the melted fugar is of 
a yellow colour; and at the furface is an oil of the fame 
colour, of a fharp tafte and penetrating fmell, very com- 
buftible, leaving a mark upon flufFs, ibluble in oils, al¬ 
cohol, and fulphuric ether, and with alkalis forming 
foap: this is the true fweet oil of wine. Deyeux con¬ 
cludes that this oil is the caufe of the yellow colour of 
nitric ether. 
The refidue of nitric ether is of a lemon yellow colour, 
its fmell is acid and aromatic, and its tafte is penetrating, 
and refembles that of diftil led vinegar. It affords, by dif¬ 
tillation, according to Baume, a clear liquor of a milder 
tafte than that of nitric ether, being an agreeable acid, 
which reddens fyrupof violets, unites with water in all 
proportions, and effervefces with carbonat of potafli. The 
retort contains a yellow friable matter, of the appearance 
of amber, which attracts the humidity of the air, becomes 
of a pitchy confiltence, and is foluble in water without 
rendering is mucilaginous. This, which Baume calls a 
gummy laponaceous fubftance, if the diftillation be con¬ 
tinued, affords a few drops of a very clear acidulous fluid, 
of an oily confiltence, and flightly empyreumatic fmell. 
A fpongy, brilliant, taftelefs, very fixed, coal remains. 
Bucquet affirms, that, if the liquor whiclftremains after 
the formation of nitric ether be evaporated, it affumes 
the confiltence of a mucilage, and at the end of a certain 
time affords faline cryftals refembling hairy caterpillars, 
which have been called cryftals of Hiseme, from the name 
of the chemift who firft deferibed them. It has fince been , 
difeovered, that this refidue is the oxalic acid, which 
proves that the combuftible bafeof thrit acid is contained 
in alcohol. 
The nature of the gas difengaged, during the diftilla¬ 
tion of a mixture of alcohol and nitric acid, lias been 
lately inveftigated by the Dutch chemifts. The produc¬ 
tion of this gas, is more or lefs rapid according to the 
ftrength of the acid, and of the alcohol. After'this gas 
ceafed to be produced, nitrous gas was given out, and the 
liquor at laft was found to confift chiefly of acetic acid. 
Little or no ether is formed during this procefs. The 
gas has a difagreeable and etherous fmell, which it did 
not lofe by (landing ; it burned (lowly and with a yel- 
lowifti flame, by bringing it into contaft with the flame 
of a candle. It is wholly abforbed by water, which ac¬ 
quires the fmell of the gas. Alcohol appears to abforb it 
in a (horter time, and in a greater quantity than water. 
It is abforbed, though (lowly, by a folution of potafh. 
The fulphuric and muriatic acids difengage it from this 
combination, with its properties unchanged; ammoniac 
lias no a£tion on this gas. Oxygen does not alter it, but 
if a mixture of thefe fluids be fired, a very violent explo- 
fion takes place. Sulphuric, nitric, and muriatic, acids, 
change this gas into nitrous gas. By palling it through 
glafs tubes red hot, a'thick vapour came out of tire tubes, 
which precipitated lime water, and was inflammable. The 
inftde of the tubes was covered with an empyreumatic oil. 
The gas was now no longer abforbable by water,and it had 
the fmell of nitrous gas. Oxygen,and the oxygenated mu¬ 
riatic acid, produced in it the red vapours, which are Cure 
marks of the formation of the nitric acid; the refidue 
was carbonated hydrogen gas. Thefe experiments feem 
fufficient to ftiow, that this fubftance was a compound of 
nitrous gas, and of a fubftance confiding of hydrogen 
and carbon. 
By mixing this inflammable gas, with oxygenated mu¬ 
riatic gas, a very coiiflderable diminution of volume took 
place. In this experiment, the oxygenated muriatic acid 
converted the nitrous gas into nitric acid,'and was itfelf 
reduced to the (fate of ordinary muriatic acid ; for the li¬ 
quor which is formed, and which trickles down the fides 
of the veffels in which the gafes are mixed, affords cry¬ 
ftals of-the nitrat and muriat of potafli, when that alkali- 
is added. 
The Dutch chemifts are of opinion, that, befides the 
nitrous gas, the other conftituent part of this inflamma¬ 
ble gas is ether, though in a (fate fomewhat different from, 
the ordinary (fate of that fubftance. They call this gas, 
therefore, etherized, or etherated nitrous gas. If one part 
of nitric acid be mixed with fix of alcohol, and digefted- 
on zink, the gafeous oxyd of azot is firft difengaged, and 
afterwards this peculiar kind of inflammable gas. When 
this gas was expofed to the re-agents which take oxygen 
from nitrous gas, fuch as a folution of copper in ammo¬ 
niac, of muriat of tin, or an alkaline fulphure, it was 
converted into the gafeous oxyd of azot, which having 
no tendency to combine with the other, quitted it, and 
of courfe, reftored to it its primitive inflammability. 
Muriatic ether is produced by the following procefs 
from Pelletier and Klaproth : Pelletier’s method is to 
put eight parts of manganele and twenty-four parts of 
muriat of foda into a large tabulated retort; add twelve 
parts of fulphuric acid and eight of alcohol, and proceed 
to diftillation ; and a liquor will be produced, from which 
■31' °f pure ether may be obtained by diftillation and rec¬ 
tification. A good ether may be obtained by pafling 
oxygenated muriatic acid through alcohol: it is even a 
(horter procefs than the foregoing. 
Klaproth diftilled equal parts of alcohol and oxyge¬ 
nated muriat of tin. The refidue in the retort, is' a 
brown, tranfparent, refmous, mafs ; what paffes over ftill 
contains acid holding tin iff folution 1 this muriat is to 
be feparated by means of caultic potafh, and the liquor 
diftilled a fecond time. This ether is very volatile, fvvims 
upon water, catches fire at a diftance, takes up gold dif- 
folved in nitro-muriatic acid, and iron from oxygenated 
muriatic acid. 
The ACETOUS FERMENTATION. 
Boerhaave called the operation by which wine paffes to 
the acid (late by the name of acetous fermentation. There 
are three conditions necefi’ary to the acetous fermentation. 
1. The prefence of a mucilage or mucous matter. 2. A 
heat from 18 to 25 0 , (75 to 90 0 of Fahrenheit.) 3. The 
prefence of oxygen gas. 
All wines are equally proper to make vinegar; it is made 
alfo with cider and perry. Gumsand amylaceous fecula, 
difi’olved in boiling water, are capable of undergoing the 
acid fermentation. Chaptal made vinegar by cohering the 
carbonic acid which was difengaged during the vinous 
fermentation ; he obtained it alfo by mixing alcohol with, 
(our milk. Vinegar may be drawn from the lees of wine; 
it mu ft be (queezedin the prefs, then put into calks, and 
left to ferment. 
Boerhaave, in his Elements of Chemiftry, has deferibed 
a very good procefs for making vinegar. Two large calks 
are provided, and a falfe bottom of wicker is fixed, at fome 
diltance from the bottom, within each, on which vine- 
branches and grape-ftatks are fpread; wine is then poured 
in 5; 
