In the production of sole-leather, fleshing machines have not as yet come into very general use. This may be accounted for by the fact that if used before liming a rough flesh is produced, which is unsightly on sole-leather, and which cannot well be afterwards improved, while something of the same objection attaches to fleshing after liming, with the added disadvantage that the hide is too much pressed, and is not easy to plump again, so as to make a satisfactory sole-leather. In America, both sole- and dressing-leathers are usually tanned in sides, the hide being cut down the centre of the back. In England, the hide is usually “rounded” for sole-leather into “butts” or “bends” and “offal,” as shown in Fig. 33. The rounding is done by hand with a sharp knife on a table, and in some of the best tanneries frames made of wood or metal are employed, to mark the sizes required. The chief advantage of rounding before tanning is that the different parts of the hide can be differently tanned, and appropriated to the purposes for which they are most suitable. The offal is now frequently split and worked up for light leather, or in other cases is tanned with a cheaper and more rapid tannage than the butts. [Illustration: FIG. 33.--Diagram of Hide.] Dressing leather is more frequently rounded after tanning, according to the purposes for which it may be required. CHAPTER XIII. _DELIMING, BATING, PUERING AND DRENCHING._ Although lime is in many respects the most useful and satisfactory means of loosening hair from hides and skins, it is of the greatest importance that it should be completely removed when it has done its work, since its action on tannins is most injurious, and it is often harmful in tawing. For soft leathers it is also necessary that the skin should be brought from a swollen to a soft and flaccid condition. In practice this is mainly accomplished for dressing leathers by bating, puering and drenching; while sole-leather and strap-butts are only too frequently left to chance, and to the natural acidity of the tanning liquors. _Bating_ consists in handling, or steeping the goods in a weak, fermenting infusion of pigeon- or hen-dung for a time usually extending over some days, and is applied to the heavier classes of dressing leather, such as “common” and shaved hides, kips and calf-skins. _Puering_ is a very similar process, applied to the finer and lighter skins, such as glove- and glacé-kids and moroccos, in which dog-dung is substituted for that of birds, and, as the mixture is used warm and the skins are thin, the process is generally complete in a few hours at most. Neither bating nor puering are very effective in removing lime, and seem to act principally by some direct effect of the bacterial products on the swelling of the pelt.