DOI Seite / Zitierlink:
https://doi.org/10.11588/diglit.11636#0351
AND LOWER EGYPT. 321
salt, and, finally, to a small degree of vitriolic
tartar. In the magazines two sorts are to be dis-
tinguished; the common and the suit ami: this an-
swers to the word royal, by which are designated in
France several commodities of a superior quality.
This j«//«?/-natron is whiter, better crystallized,
and more pure than the common; it is conse-
quently more powerful, and, in the use of it, a
smaller quantity is employed.
This mineral alkali possesses the same proper-
ties with the vegetable alkali, or salt-wort; but it
possesses them in a superior degree of virtue. Its
principal use is for the bleaching of thread and
cloth. The following is the method which I have
seen pursued at Rossetta. The skeins of thread
are laid in a large copper built in mason-work ; a
layer of natron is placed upon them : afterwards
cold water is poured on it, in a sufficient quantity
to soak the thread and the natron. They are thus
left altogether for the space of three days, at the
end of which the thread is drawn out, and sus-
pended on sticks placed over the ketlle. When
it is drained, a fire is kindled under the copper,
and the water in which the thread had been steep-
ed with the natron is made to boil, afler having
some lime added to it. The thread is dipped in
it, and washed several times, stirring it through
this hot lye, without leaving it there. It is im-
vol. 1, x mediately
salt, and, finally, to a small degree of vitriolic
tartar. In the magazines two sorts are to be dis-
tinguished; the common and the suit ami: this an-
swers to the word royal, by which are designated in
France several commodities of a superior quality.
This j«//«?/-natron is whiter, better crystallized,
and more pure than the common; it is conse-
quently more powerful, and, in the use of it, a
smaller quantity is employed.
This mineral alkali possesses the same proper-
ties with the vegetable alkali, or salt-wort; but it
possesses them in a superior degree of virtue. Its
principal use is for the bleaching of thread and
cloth. The following is the method which I have
seen pursued at Rossetta. The skeins of thread
are laid in a large copper built in mason-work ; a
layer of natron is placed upon them : afterwards
cold water is poured on it, in a sufficient quantity
to soak the thread and the natron. They are thus
left altogether for the space of three days, at the
end of which the thread is drawn out, and sus-
pended on sticks placed over the ketlle. When
it is drained, a fire is kindled under the copper,
and the water in which the thread had been steep-
ed with the natron is made to boil, afler having
some lime added to it. The thread is dipped in
it, and washed several times, stirring it through
this hot lye, without leaving it there. It is im-
vol. 1, x mediately