There are other matters connected with this subject which belong rather to the commercial and agricultural business of the country, but are not wholly devoid of interest to the naturalist and chemist. I allude to the quality and quantity of tanning materials as produced and influenced by latitude, locality, and climate. In the Eastern, Northern, and Western States the quality and quantity of tan barks are far inferior to those of the Middle, Southern, and South-western. The facilities and natural resources of the South for manufacturing leather, over those of the North, as far exceeds those of the latter, as the actual amount of leather and shoes manufactured by the North exceeds those manufactured by the South. The South, in fact, ought to furnish the North with leather; and should, moreover, produce all the sumac needed for home consumption, both for dyeing and tanning, of which we now import large quantities. By procuring from the coast of the Mediterranean the best varieties of sumac, viz., the Rhus Coriana and the Rus Cotinus—the former used chiefly in tanning, and the latter in dyeing, the South might grow enough in a few years for export, and find it a profitable branch of industry. CHAPTER III. PRACTICAL HINTS ON TANNING. The Hon. Zadock Pratt, one of the largest Tanners in the State of New York, has given some very valuable information concerning the various tanning processes which his experience and knowledge have afforded him. We shall select a few of the most important as furnished by him to Morfit’s valuable work. Skins with the hair on are first soaked in cold water for forty-eight hours, and are then subjected to the action of the machine (Monier & Ray’s Mill) for an hour and a half; exposure for which time is generally sufficient to render them pliable. Eight or ten skins, according to their size and thickness, are generally contained in the apparatus. The water is then allowed to drain off, a sufficient quantity of cream of lime is poured in and the skins are again beaten for four hours, when they are taken out and piled up. After having been left to drain for five hours in this position, they are again fulled for a time in the machine, and then are deprived of their hair and fleshed by the workmen. They are then beaten for an hour and a half in the machine, and cleaned and scraped with the slate. In order to remove the lime, some of which remains attached to the skins, they are now soaked in water containing one hundredth part of sulphuric acid, and, after being constantly stirred in this liquid for an hour, are washed and rinsed in running water.