wire our analysis. The saline contents indi- 
cated bv it are supposed to be freed from 
their water of crystallization ; in which state 
only they ought* to be considered, as Mr. 
Kirwan has very properly observed, when 
we speak of the saline contents of a mineral I 
water. 
Having by this formula ascertained pretty ; 
nearly the proportion of saline contents in 
the water examined, and having by the tests 
described in the last section, determined the 
particular substances which exist in it, let us 
now proceed to ascertain the proportion of 
each of these ingredients. 
I. The’different aerial fluids ought to be first 
separated and estimated. For this purpose a 
retort ought to be filled two-thirds with the 
water, and connected with a jar full of mer- 
cury, standing over a mercurial trough. Let 
the water be made to boil for a quarter of an 
hour. The aerial fluids will pass over into 
the jar. When the apparatus is cool, the 
quantity of air expelled from the water may 
be determined either by bringing the mer- 
cury within and without the jar to a level ; or 
if that cannot be done, by reducing the air 
to the proper density. The air of the retort 
ought to be carefully subtracted, and the 
jar must be divided into cubic inches and 
tenths. 
The only gaseous bodieshn water are com- 
mon air, oxygen gas, azotic gas, carbonic 
acid., sulphureted hydrogen gas, and sulphur- 
ous acid. The last two never exist in water 
together. The presence of either of them 
must be ascertained previously by the appli- 
cation of the proper tests. If sulphureted 
hydrogen gas is present, it will be mixed with 
the air contained in the glass jar, and must 
be separated before air is examined. For this 
purpose, the jar must be carried into a tub 
of warm water, and nitric acid introduced, 
w hich will absorb the sulphureted hydrogen. 
The residuum is then to be again put into a 
mercurial jar and examined. 
If the water contains sulphurous add, this 
previous step is not necessary. Introduce 
into the air a solution of pure potass, and 
agitate the Whole gently. The carbonic 
acid and sulphurous acid gas will be absorb- 
ed, and leave the other gases. Estimate the 
bulk of this residuum ; this, subtracted from 
the bulk of the whole, will give the bulk of 
the carbonic acid and sulphurous acids ab- 
sorbed. . , , 
Evaporate the potass slowly nearly to dry- 
ness, and leave it exposed to the atmosphere. 
Sulphat of potass will be formed, which may 
be separated by dissolving the carbonat ot 
potass by means of diluted muriatic acid and 
liltring the solution. One hundred grains 
of sulphat of potass indicate thirty grains of 
sulphurous acid, or 412./ -.’ cubic inches ol that 
acid in the state of gas. The bulk of sulphu- 
rous acid gas ascertained by this method, 
subtracted from the bulk of the gas absorbed 
by the potass, gives the bulk of the carbonic 
acid eras. Now one hundred cubic inches of 
carbonic acid, at the temperature of 60°, and 
barometer at 30 inches, weigh 46.393 grains. 
Hence it is easy to ascertain its weight. 
The air which remains after the separation 
of the carbonic acid gas is to be examined 
by the different eudiometrical methods. 
\Vhen a water contains sulphureted hy- 
drogen gas, the bulk of this gas is to be as- 
■ WATERS. 
ccrtained in the following manner : Fill 
three-fourths of a jar with the water to 
be examined, and invert it in a water 
trough, and introduce a little nitrous gas. 
This gas, mixing With the air in the up- 
per part of the jar, will form nitrous acid, 
which will render the water turbid, by de- 
composing the sulphureted hydrogen and 
precipitating sulphur. Continue to add ni- 
trous gas at intervals as long as red fumes ap- 
pear, then turn up the jar and blow out the 
air. If the hepatic smell continues, repeat 
this process. The sulphur precipitated indi- 
cates the proportion of hepatic gas in the 
water; one grain of sulphur indicating the 
presence of 3.33 cubic inches ot that gas. 
H. After having estimated the gaseous 
bodies' the next step is to ascertain the pro- 
portions of the earthy carbonats. For this 
purpose it is necessary to deprive the water 
of its sulphureted hydrogen, if it contains 
any. This may be done, either by exposing 
it to the air for a considerable time, or by 
treating it with litharge. A sufficient quan- 
tity of the water thus purified (if necessary) 
is to be boiled for a quarter of an hour, and 
filtred when cool. The earthy carbonats 
remain on the filtre. 
The precipitate thus obtained may he car- 
bonat of lime, of magnesia, of iron, of alu- 
mina, or even sulphat of lime. Let us sup- 
pose all of these substances to be present to- 
gether. Treat the mixture witli diluted mu- 
riatic acid, which will dissolve the whole ex- 
cept the alumina and sulphat of lime. Dry 
this residuum in a red heat, and note the 
weight. Then boil it in carbonat of soda ; 
saturate the soda with muriatic acid, and boil 
the mixture for half an hour. Carbonat of 
lime and alumina precipitate. Dry this pre- 
cipitate, and treat it with acetic acid. The 
lime will be dissolved and the alumina will 
remain. Dry it and weigh it. Its weight 
subtracted from the original weight gives the 
proportion of sulphat of lime. 
The muriatic solution contains lime, mag- 
nesia, and iron. Add ammonia as long as a 
reddish precipitate appears. The iron and 
part ol the magnesia are thus separated. Dry 
the precipitate, and expose it to the air for 
some time in a heat of 200° ; then treat it 
with acetic acid to dissolve the magnesia, 
which solution is to be added to the muriatic 
solution. The iron is to be redissolved in 
muriatic acid, precipitated by an alkaline car- 
bonat, dried, and weighed. 
Add sulphuric acid to the muriatic solu- 
tion as long as any precipitate appears ; then 
heat the solution and concentrate. Heat the 
sulphat of lime thus obtained to redness, and 
weigh it. One hundred grains of it are equi- 
valent to 70 of carbonat of lime dried. Pre- 
cipitate the magnesia by means of carbonat ot 
soda. Dry it and weigh it. Rut as part re- 
mains in solution, evaporate to dryness, and 
wash the residuum with a sufficient quantity 
of distilled water to dissolve the muriat of 
soda and the sulphat of lime, if any should 
be still present. What remains behind is 
carbonat of magnesia. A eigh it, and add its 
weight to the former. The sulphat of lime, 
if any, must also be separated and weighed. 
III. Let us now consider the method of as- 
certaining the proportion of mineral acids or 
alkalies, if any should be present uncombin- 
ed. The acids which may be present, (omit- 
5 U 2 
*91 
ting the gaseous) are the sulphuric, muriatic* 
and borac.c. 
1. ■ proportion of r dphuric ac'd Is 
easily determined. Saturate it with barytes 
water, and ignite the precipitate. One hun- 
dred grams of sulphat of bar. te; thus formed 
indicate 23.5 of real sulphuric acid. 
2. Saturate the muriatic acid with barytes- 
water, and then precipitate the barytes by 
sulphuric acid. One hundred parts .of the 
ignited precipitate are equivalent to 21 grains 
of real muriatic acid 
3. Precipitate the boracic acid by means of 
acetat of lead. Decompose the borat of lead 
by boiling it in sulphuric acid. Evaporate to 
dryness. Dissolve the boracic acid in alco- 
hol, and evaporate the solution ; the acid lett 
behind may be weighed. 
4. To estimate the proportion of alkaline 
carbonat present in a water containing it, sa- 
turate it with sulphuric acid, and note the 
weight of real acid necessary. Now 100 
grains of real sulphuric arid saturate 121.4* 
potass, and 78.32 soda. 
IV. Let us now consider the method of 
ascertaining the proportion ot the different 
sulphats. These are six in number ; the 'al- 
kaline sulphats, and those of lime, alumina, 
magnesia, and iron. 
1. The alkaline sulphats may be estimated 
by precipitating their acid by means of nitrat 
of barytes, having previously freed the water 
of all other sulphats. For 170 grains ot ig- 
nited sulphat of barytes indicate 100 grains 
of dried sulphat of soda ; while 136.36 grains 
of sulphat of barytes indicate 100 of dry sul- 
plnit of potass. 
2. Sulphat of lime is easily estimated by 
evaporating the liquid containing it to a few 
ounces (having previously saturated the' 
earthy carbonats with nitric acid), and pre 
cipitating the sulphat of lime by means of 
weak alcohol. It may be then dried and 
weighed. 
3. The quantity of alum may be estimated 
by precipitating the aLunfina by carbonat of 
lime or of magnesia (if no lime is present in 
the liquid). Twelve grains of the alumina 
heated to incandescence indicate one hundred 
of crystallized alum, or forty -nine of the dried 
salt. 
4. Sulphat of magnesia may be estimated, 
provided no other sulphat is present, by pre- 
cipitating the arid by means ot a barytie 
salt, as "tOO parts of ignited sulphat of ba- 
rytes indicate 52.11 of sulphat ot magnesia.- 
If sulphat of lime, and no othef'sulphat ac- 
companying it,, this lust may be decomposed, 
and the lime precipitated by carbonat of mag- 
nesia. The weight of the lime thus obtained 
enables us to ascertain the quantity^ of sulphat 
of lime contained in the water. r l he whole 
sulphuric arid is then to be precipitated by 
barytes. This gives the quantity ot sulphuric 
acid ; and subtracting the portion which be- 
longs to the sulphat of lime, there remains 
that which was combined with the magnesia, 
from which the sulphat ot magnesia may be 
easily estimated. 
If' sulphat of soda is present, no earthy 
nitrat or muriat can exist. Therefore, if no 
other earthy sulphat is present, the magnesia 
may be precipitated by soda, dried, and 
weighed ; 36.68 grains of which indicate 100 
grains of dried sulphat of magnesia. The 
same process succeeds when sulphat of lime 
accompanies these two sulphats ; only in that 
