100 TECHNICAL QUALITIES OF THE TREES 



Tideland spruce :- Lumber; construction; outer finish; woodenware; paper pulp. 



Hemlock: -Lumber; dimension stuff ; construction timbers; shingles; railroad ties; fencing; paper pulp 

 and fibre ; bark for tanning. 



Douglas fir: -All building lumber; furniture; lath; construction timbers; railroad ties; trestle bridges; 

 piles; car material, notably sills; ship building; masts; flagpoles; mining timber; bark sometimes used 

 for tanning. 



Firs: -Paper pulp and fibre; corduroying; local lumber; packing cases; cooperage; interior finish; 

 mine props. 



Tamarack (Eastern):- Fence posts; telegraph poles; soda fibre; ship's knees; railroad ties. 



Tamarack (Western):- Posts; railroad ties; car construction; dimension stuff; building lumber. 



(C) TROPICAL AND SUBTROPICAL TIMBER. 



Yucca: — Paper pulp and fibre for ropes; pin cushions. 



Eucalyptus: -Street paving; railroad ties; mine props; piles; ship building; waggon making; orchard 

 paling. 



Mangrove: — Bark very rich in tannin. 



Palmetto: -Wharf piles; pin cushions; brushes. 



Lignum vitae:- Bowling balls; blocks for pulleys; fine interior finish and furniture; railroad ties in 

 Panama. 



Teak: — Ship building and flooring; railroad cars; street paving. 



West India cedar:- Racing boats; cigar boxes. 



Olivewood: — Turnery ; inlaying; furniture; backs of hair brushes; wood carving. The fruit yields the 

 best oil for table use. 



Quebracho: -Tanning; paving; railroad ties. 



Lancewood : — Fishing rods. 



Mahogany :- Furniture; ship building; pianos; interior finish. 



Fustic wood:- Dyeing. 



PARAGRAPH XVIII. 

 TECHNICAL QUALITIES OF THE TREES. 



(A) BOTANICAL STRUCTURE OF THE TREES. 



I. Botanical structure of hardwoods. The cells forming the woody tissue are:- 



(a) Ducts (pores, vessels) formed by the resorption of the partition walls in a vertically running 

 string of cells. Such ducts are characteristic of hardwoods; 



(b) Sclerenchyma, cells of heavy walls and small lumina, usually forming long fibres; 



(c) Parenchyma, cells of thin walls and large lumina, frequently containing grains of starch. 



Medulla or pith is found in the central column, in the primary, secondary, tertiary rays and (rarely) 

 in medullary spots (birch). The central pith is:- 



Heavy in ash, maple, elder, catalpa. 

 Triangular in birch, alder. 

 Quinquangular in hornbeam. 



Broad leaved species are called " ring porous," if the spring wood of the annual ring contains strikingly 

 large pores, or else "diffuse porous," if the ducts, are more evenly distributed over the entire ring. Sapwood 

 and heartwood are m.erely distinguished by a difference of color, caused by incrustations of pigments, 



