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and a consequent reduction of the price, without any improvement in the quality of the leather, but rather the reverse. This has given rise to a strong prejudice in the minds of persons connected with the leather trade, against leather tanned by any quick process. The difficulty of bringing the tannin, or tannic acid, immediately and effectually into contact with the gelatinous fibre of the skin, arises from several causes, which it may be useful to enumerate.
“In preparing the skins and hides for the tanpit, they are steeped for a considerable time in a solution of lime, to remove the hair and epidermis. In this process, the skin imbibes a considerable quantity of lime, which has the effect of either removing from the hide or skin, a portion of the gelatinous substance, in the form of soluble gelatine, or, of altering the gelatinous fibre, so as to render it incapable of speedily and effectually combining with the tannin or tannic acid, and the pores of the skin are so impregnated with lime, as to prevent the tanning principle from operating freely, or reaching the heart of the skins.
“ The great object to be obtained, therefore, is to find out some means of removing these obstructions and antagonistic principles, and of bringing about a speedy and effectual combination of the fibre of the hides or skins, and the tanning matter, and thus produce in a short space of time, leather superior in weight, quality, and durability, to any yet produced. The object of my improvements, is to remove these difficulties, and obstructions, either by extracting the lime with which hides and skins are impregnated in the process of removing the hair, or removing the same without the use of lime, by means not hitherto attempted.
The old plan of using lime, by which, no doubt, the skin was injured to an extent we never before supposed, and the consequent process in the tanyard, of puring, as it is termed, by means of the dung of animals
a process the most filthy and disgusting, one would have thought, that could be imagined-gives way to Dr. Turnbull's discovery of “sugar and sawdust." This simple and delicate preparation, we are told, is more effectual; and “you may drink it,” say the workmen, “for it is fit for any
table in the land." The new method is to prepare a mixture of sugar and water, and sawdust mit may be of any other substance containing saccharine matter, such as beetroot, potatoes, turneps, honey, &c. The action of the sugar and pyroxalic, or wood spirit, is 80 rapid, that the skins are rendered fit to receive and imbibe the tannic acid; and thus the operation
of tanning is perfectly accomplished in a very short time. The leather thus produced is considerably heavier, and of finer quality, than any leather produced by the present method of tanning. This method of removing the lime is of immense importance, as it not only improves the leather in weight and durability, but enables the tanner to produce a superior article in a much less space of time, and at a much less expense, than heretofore. Attempts have been made to remove the lime by a preparation called grainer, which is mainly composed of the dung of animals. This being of a strong alkaline nature, necessarily destroys a considerable portion of the gelatinous matter, in the operation of extracting the lime ; at the same time much injury is done to the texture of the skin by its rapid action in causing decomposition, and destroying the grain side of the skin, especially in summer. It must be obvious, however, that the moment the skin imbibes lime in any quantity, its effect and influence on the hide or skin are to a considerable extent permanent and destructive.
The advantages of the new method appear to be, first, à great additional weight of leather, especially in calfskins ; second, leather of much better quality, soft and not liable to crack or strain; third, a considerable diminution in the expense; and fourth,
the tanning is effected in one quarter of the time consumed by the present mode of tanning.
These improvements will, it is needless to say, prove of immense importance to our home manufacture, and now that the true principles of tanning skins comes to be understood, many other improvements will gradually suggest themselves. The Rouel leather, which is the name given to it by the doctor, is certainly the best article ever produced in England (I speak now of calfskin), and works up as fine or even finer than the French, without its accompaniment of dubbing, or its impost of 30
In •Queen Elizabeth's time, parliament busied itself much in matters of “ leather and prunella ;”. numerous enactments being made, especially in reference to the former. A letter to lord-treasurer Burleigh, by W. Fleetwood, recorder of London, explains the opposition of the tanners to some enactments against them : “the one for lymyng [an old grievance, after all, this lyming), the other raisyng." He says: "All the excellencie and conning of a tanner consisteth in skilfull making of his owes [lyes ;] surelie they must be many and severall and one stronger than another. The time of changing of the lether from one owes must be timed at proscribed hours, or else the lether will be utterly
spoiled. My Lo, there be an infinite number of rules to be observed in tanning, the few which tanners did ever conceive, much less the parliament, who conveyed their information of such whome nowe I do by experiens knowe not to be skilfull.” A conclusion which many of good Queen Victoria's as well as Queen Bess's subject have arrived at, after parliamentary evidence and enactment, in matters which history, experience, and philosophy, have long since taught us, flourish best by being let alone.