NOTES OX TANNING SUBSTANCES. 291 



thirds of its length of 6 or 9 feet. The bark is of a grey colour when young, 

 but grows lighter when old, and is generally covered with moss ; the leaves 

 are 6 or 8 lines long, flat, irregularly disposed in two ranks, and downy at 

 their unfolding ; its flowers, which appear in May, are preceded by cones of 

 a dark ash colour. The bark is taken from the tree in June, and half of 

 the epidermis is shaved off before it is ground. It imparts its red colour 

 to leather made with it, which is said to be inferior to that tanned with 

 oak bark."— (Morfit.) 



The 'Montreal Commercial Advertiser' for April 1859 states "that 

 a company is about to be formed in Upper Canada to work a patent 

 granted to Mr Abraham Steers for extracting the tanning principle 

 from hemlock bark, with a view to its exportation for the use of foreign 

 tanneries. By this process, the astringent properties of a cord and a 

 half are to be concentrated into a forty-gallon cask of extract." Hem- 

 lock bark is one of the staple tanning substances used in North 

 America. 



Larch Bark (Larix Europaius). — The bark of the common larch is 

 much used for tanning basils, hog and other skins, leather for bookbind- 

 ing, &c, principally in Scotland, where the tree is abundant : it is also used 

 in England, but only to a small extent, as the supply of bark is limited. 

 The trees of this tribe are common in North America, where the bark is 

 used for tanning. 



Betulace^e, or Birchworts, are " inhabitants of the woods of Europe, 

 Northern Asia, the Himalayas and North America, and even making their 

 appearance on the mountains of Peru and Columbia, and the Antarctic 

 regions. They appear capable of existing up to the last limits between land 

 and eternal snow." 



Birch Bark (Betula alba).— This bark is used in Scotland (and else- 

 where) for tanning basils and other light skins, though not to any great 

 extent. The empyreumatic oil extracted from this bark is employed in 

 dressing Russia leather, and is said to give it its well-known smell. Birch 

 bark is used by the Laplanders for tanning: they extract the tannin by 

 boiling the bark, but usually allow the liquor to cool before immersing 

 the hides. 



Alder Bark (Alnua glutinosa). — This tree grows in wet, marshy places, 

 often by rivers. The bark is used for tanning sheep-skins for rugs, &c, but 

 it cannot be considered as one of the staple tanning materials of this coun- 

 try : it is used for dyeing black by country people. 



Corylace^e, or Mastworts, are " inhabitants of the forests of all the 

 temperate parts of the continents both of the Old and New World ; ex- 

 tremely common in Europe, Asia, and North America; more rare in 

 Barbary, Chile, and the southern parts of South America, and wanting 

 at the Cape. The species which are found within the tropics of either 

 hemisphere are chiefly oaks and chestnuts, which abound in the high lands, 

 but are unknown in the valleys of equatorial regions. The most southern 

 genus is the beech, of which many species occur in the lower parts of 



u 2 



