The so-called silicated soap, of which large quantities are now manufactured, is made by combining silicate of soda with hard soap in the hot and pasty state; in this way from 10 to 30 per cent. of the silicate may be introduced. Such soap possesses, according to Dr. Ure, very powerful detergent qualities, but it is apt to feel hard and somewhat gritty in use. The silicated soda is obtained by boiling ground flints in a strong caustic lye. Many substances are used to adulterate soap, such as potatoe-starch, clay, &c., for which improvements, as they are termed, numerous patents have been granted in this country.
In Great Britain the hard kind of soap is chiefly made at Liverpool and London, but in considerable quantities also at Runcorn, Bristol, Brentford, Hull, Bromsgrove, Plymouth and Sethwick, and at Glasgow and Leith in Scotland; the soft soap is made principally at Liverpool, Glasgow and Bradford; and silicated soap is likewise extensively manufactured at Liverpool.
From the excise returns, it appears that 140,712,535 pounds of hard, 9,788,851 pounds of soft, and 3,921,862 pounds of silicated soap were made in England in 1841; and 10,708,464 pounds of hard, and 4,535,030 pounds of soft soap in Scotland; making in all 169,666,742 pounds, which is an increase of about 30 per cent. since 1832273.
The excise duty on soap was first imposed in Great Britain in 1711, when it was fixed at 1d. per pound. It was raised in 1713 to 1½d. per pound; and again, in 1782, when hard and soft soap were first distinguished, the former being rated at 2¼d., and the latter at 1¾d. per pound. In 1816, that on hard soap was increased to 3d. per pound. But since May 31, 1833, the duty has been 1½d. per pound on hard soap, and 1d. per pound on soft. In 1839, the number of soap manufacturers in England was 177; in Scotland 19; and in Ireland 183. Each requires an annual license, costing 4l.
An allowance of duty is made on soap used in the woollen, silk, flax, and cotton manufactures, which in 1841 was granted on 10,190,160 pounds of hard, and 9,090,184 pounds of soft soap; the allowances amounting to 78,112l. In the same year the net amount yielded by the soap-duty to the public revenue was 815,864l. Ireland is not subject to the soap-duty.
The soap-maker was formerly subjected to an arbitrary and vexatious interference from the excise; but of late years the regulations have been greatly improved, and there is now no superintendence of the process of manufacture, which may be conducted in any way and of any material.]
MADDER
This plant, the root of which is either dried and bruised, or used fresh, for dyeing red, has a weak, square, jointed stem; and rises to the height of eight feet when supported, otherwise it creeps along the ground. At each joint there are from four to six leaves, about three inches in length, almost an inch broad in the middle, and pointed at both ends. The upper side of the leaves is smooth; but the middle nerve of the under side is armed with small rough prickles; and others of the same kind may be found on the stem. On this account, the leaves, which drop annually, adhere readily to other bodies, like those of the asperugo. The branches, which in June bear flowers divided into four yellow leaves, proceed from the joints. The fruit, a kind of berry, which, towards the time of its ripening, though that seldom happens among us, is first of a brownish colour, and then black, contains a round seed. The roots grow sometimes to the thickness of one’s finger, push themselves deep into the earth, are surrounded by many small fibres, have a yellowish-red pith, and are covered with a black bark or rind. This plant grows wild in the Levant, as well as in Italy, the southern parts of France, and in Switzerland. The cultivated kind is well known, and is propagated with much advantage in various countries of Europe.
When one compares this short description with what Dioscorides says of a plant which he calls ereuthodanon, it will be readily seen that he meant our madder. He even compares its long square stem, armed with a great many hooks, to that of the asperugo; and he tells us that the leaves stand in the form of a star around the joints. The fruit was at first green, then red, and lastly black. The thin long roots, adds he, which are red, serve for dyeing; and on that account the cultivated kind (he must therefore have been acquainted with the wild sort) is reared with much benefit in Galilee, around Ravenna in Italy and in Caria, where it is planted either among the olive-trees, or in fields destined for that purpose. It is remarked in some manuscripts, that this plant had a name given it by the Romans, which, as Marcellus Virgil observes, meant the same thing as Rubia sativa, and that it was called in Etruria Lappa minor, doubtless because, like the bur, it adhered to other bodies. On account of the colour which it communicated, it was called also sometimes cinnabaris274.
In opposition to this asserted identity I find only one doubt; namely, that among those plants which, on account of the position of their leaves, were called stellatæ, and which were all so like that we must reduce them to one natural order, there are more sorts, the roots of which dye red, and which on that account are very improperly called wild madder. Why, therefore, should the plant of Dioscorides be our madder, and not some other plant of the like nature? For this reason, in my opinion: because the ancients, who were acquainted with all these plants, which grew wild in their lands, were equally prudent as the moderns, and cultivated that kind only which was the most productive or beneficial, viz. our Rubia tinctorum.
This opinion will be strengthened by comparing the accounts given of that plant by other ancient writers. Theophrastus agrees almost perfectly with Dioscorides; and adds, that it did not grow upright, but was fond of reclining. The comparison, therefore, with the leaves of ivy cannot be just; but that I shall leave to the critics. Pliny says expressly, that the erythrodanum or ereuthodanum was in his mother-tongue called rubia; and that its red roots were used to dye wool and leather red275.
In the middle ages this plant was called varantia, a name which must have arisen from verantia. The latter means the real, genuine dye; as aurantia signified a golden yellow. Till the year 1736, this plant was little regarded, except among dyers, farmers and merchants, who purchased it from the farmers, in order to sell it to the dyers with profit; and among a few herb-dealers and physicians, who, on the authority of the ancients, ascribed to it eminent virtues, which others doubted or altogether denied. In the above year, however, a property of it was discovered by accident, as usual, which rendered it an object of more attention. John Belchier, an English surgeon, having dined with a cotton-printer, observed that the bones of the pork which was brought to the table were red. As he seemed surprised at this circumstance, his host assured him that the redness was occasioned by the swine feeding on the water mixed with bran in which the cotton cloth was boiled, and which was coloured by the madder used in printing it. Belchier276, to whom this effect was new, convinced himself by experiments that the red colour of the bones had arisen from the madder employed in printing the cotton, and from no other cause; and he communicated his discovery to the Royal Society, in a paper which was printed in their Transactions.
This singularity was now soon known to all the naturalists, several of whom made new experiments, the result of which brought to light many truths useful to physiology. Besides the roots of madder, those of the Galium (yellow ladies-bed-straw) and other plants which have an affinity to madder, produce the like effects; but this is the