This vat is prepared with 13 lbs. of indigo, 17½ lbs. of madder, 4½ lbs. of bran, 9 lbs. of lime, and 4½ lbs. of potash. Having filled the vat, we heat it to about 200° Fah., and, as soon as the water is tepid, introduce 441 lbs. of pastel. The liquor becomes of a yellowish-brown color; small bubbles appear upon its surface, ordinarily at the end of four hours if the vat be heated by steam, but not until after eight or twelve hours where heat is applied by the common fire; in the latter case the mixture should be stirred every three hours. When the liquor displays the signs of fermentation, we add the above-mentioned ingredients, and cover the vat over; it is then to be set aside, stirring it every three hours, or oftener if the fermentative action be very rapid. Each time that it is stirred we are to add from 2 to 4 lbs. of lime; if fermentation proceed quickly we even use more, but in the contrary case less. After about eighteen hours, we plunge into the vat three pieces of common cloth, measuring from twenty to twenty-five ells in length each; when they have received six or seven turns, they are to be taken out again. The object of this is to remove the excess of lime from the bath. The vat is then set aside for three hours, when it is to be stirred, and 13 lbs. of indigo, with 2 lbs. of madder, added to it. We now again apply heat to the mixture. If the vat contains a superabundance of lime, it will be unnecessary to add more; otherwise we throw in a further quantity. During the night it should be covered with a cloth, and a workman left to watch it. It is usually stirred once before the morning; but if it be deficient in lime, it will require this manipulation to be more frequently repeated, and also fresh lime added to it. On the following day the stirring should be continued every three hours, and so on for the next thirty hours, taking care to heat the vat from time to time. On the morning of the fourth day the dyeing may be commenced. The temperature should be maintained at a pretty uniform point; if it be too hot, the blue takes a red reflection, by reason of the madder contained in the liquid. A vat thus prepared will last three months; we may even work it for double that period, but after the third month it appears to lose some of its indigo.