292 NOTES OX TANNING SUBSTANCES. 



South America, and in Van Diemen's. Land and New Zealand. Of the 

 former, Fagus procera is said to be a larger tree than the Araiicaria itself, in 

 whose country it grows wild." 



English Oak Bark (Quercus pedunculata and Q. sessiliflora) is preferred 

 before all other materials for tanning ; the best and highest-priced leather 

 being tanned with it. The quality of the oak bark grown in this country 

 is considered superior to that of any other part of Europe, being supposed 

 to contain a larger proportion of tannin. 



The bark season in England is usually from the middle of April to the 

 end of May ; but much depends on the weather, a few warm sunshiny days 

 being desirable before stripping, as it is essential the sap should run well, 

 for the bark contains more tannin when the sap begins to circulate. The 

 tree is generally thrown before stripping, but sometimes the bark is stripped 

 from the standing tree : in both cases the method pursued is the same. 

 The operation of barking is performed by cutting the bark round the tree, 

 and then cutting it lengthwise, peeling it off with a tool similar in shape to 

 a small oyster-shell fitted to a handle. The bark is then piled in stacks 

 about two feet high and two feet wide, each stack consisting of the bark of 

 one tree, or those felled near together. It is left thus until dry ; but care 

 should be taken to cover the tops of the stacks with large pieces of bark, to 

 preserve them from the rain. 



Besides our home supplies of oak bark, estimated at from 200,000 to 

 300,000 tons a year, 20,000 to 30,000 tons more of bark are imported 

 from the Continent, &c. 



Coppice Oak Bark. — This bark is very similar to the timber bark, but 

 lighter and thinner, and contains more tannin in proportion to its weight, 

 as it has less epidermis. It is preferred for tanning dressing leather. 



Antwerp Oak Bark. — This bark is imported "hatched" (that is, 

 chopped into pieces four or five inches long, with most of the epidermis 

 scraped off), but does not sell for quite so high a price as the English, as it 

 is supposed not to contain so much tannin. 



American Oak Barks. — The following is from the ' Shoe and Leather 

 Reporter ' of the United States : — " There are four species of oak barks 

 chiefly used in tanning. The first is the Spanish oak, which thrives in 

 Maryland, Delaware, and Virginia, and in all the States south of 41 deg. N. 

 In the Atlantic States this species is most abundant, and in Georgia and 

 the Carolinas it is known by the name of red oak ; its bark, which is thick, 

 black, and deeply furrowed, is preferred for coarse leather, which it makes 

 more pliable and of a better colour. Hemlock bark is often with advantage 

 mixed with it. In the Southern States, the Spanish oak grows to the height 

 of 80 feet, having a trunk 4 or 5 feet in diameter ; while in some of 

 the Northern States it does not exceed 30 feet in height, with a diameter of 

 5 or 6 inches. The common red oak grows abundantly in Canada and 

 in the Northern States, especially in the southern half of New York, in 

 New Jersey, in Northern Pennsylvania, and along the range of the Allegha- 

 nies. Its bark is very generally employed, though inferior in several respects 



