CARRAGEEN, OR IRISH MOSS.
This is an article used by some, and can be dispensed with altogether: it is not a necessary article. When used, it should be picked (the white being the best) and well washed; then set it to simmer in a gentle heat for an hour or two, strain it through a fine hair sieve, and it will be ready for use; but it will require a portion of the solution of gum-tragacanth to be able to do much with it.
FLEA-SEED.
This is an article but little known except to those who have occasion to use it. It is a small, brown, hard seed, in size, shape, and colour closely resembling the annoying little insect whose name it bears, and from which it may possibly derive its appellation. It produces a very strong and powerful mucilage—far stronger than that which can be obtained from linseed; and what enhances its value is that it will not so soon lose its strength or turn to water, but will keep several days. It is a great assistant, mixed with gum, in the making of French and Spanish marbles, but is a total enemy to nonpareil and drawn patterns.
To prepare it, put a quarter of a pound of the seed into a pan, pour upon it a gallon of boiling water, keep it well stirred for ten minutes, and let it stand for half an hour; then stir it again for ten minutes more, and in another half-hour add another gallon of boiling water, stirring it as before, at intervals, for one hour; after which let it remain, and the seed will settle at the bottom of the pan. When cold, pour off the top for use, and the seed will bear more boiling water, though not so much as at first. Sometimes the seed will yield a third extract; but this must be determined by your judgment, as the seed, when exhausted, will lose its viscid property, and must then be thrown away. The seed should never be stirred up after it has cooled, for it will settle without being again heated or having more boiling water added to it.
OX-GALL.
The surest way of obtaining this article genuine is by procuring it in the bladder as it is taken from the animal, if you are acquainted with any butcher upon whom you can depend. The gall from some animals is very thick, but will, after keeping some time, get thin, without at all losing its properties; in fact, gall is all the better for being kept, and is none the worse for a strong smell.
WATER.
Soft or rain water, when it can be procured, is the best adapted for all the preparations in marbling.
OF THE PREPARATIONS OR VEHICLES REQUIRED
FOR MARBLING UPON.