34 HOUGH'S AMERICAN WOODS. 



A tree of medium size and rapid growth, sometimes attaining the 

 height of 80 ft. (24 m.) and 3 ft. (0.90 m.) in diameter of the trunk. It 

 is recognizable at all seasons from its beautiful snowy white bark which 

 peels off transversely in large sheets, and which in turn may be sub- 

 divided into an indefinite number of thinner sheets. The outer surface 

 of tbe bark of very old trunks is rendered rough and ragged by the curl- 

 ing up of strips of the outermost layers. On twigs and small branches 

 the bark is of a dark brown color. 



HABITAT. A distinctively northern tree. It is found from about the 

 latitude of Pennsylvania northward to Hudson's Bay and in the north- 

 west to the arctic regions. Professor Sargent observes that it reaches a 

 higher latitude than any deciduous tree of the American forests. 



PHYSICAL PROPERTIES. Wood light, strong, tough and hard; heart- 

 wood of a reddish-brown color and sap-wood yellowish- white. Specific 

 Gravity, 0.5955; Percentage of Ash, 0.25; Relative Approximate Fuel 

 Value, 0.5940; Coefficient of Elasticity, 130557; Modulus of Rupture, 

 1065; Resistance to Longitudinal Pressure, 487; Resistance, to Indenta- 

 tion, 126; Weight of a Cubic Foot in Pounds, 37.11. 



USES. A favorite timber for small articles of wooden- ware, such as 

 clothes-pins, spools, pill-boxes, shoe-lasts, pegs, etc. It is also used for 

 wood-pulp and to some extent for furniture, especially when stained to 

 imitate cherry or mahogany. 



With the aborigines of this country this must have been the most 

 valuable of our trees, because from its bark they were able to make their 

 indispensable canoes, of such strength and lightness that one calculated 

 for four persons with their baggage is said to have weighed only from 

 forty to fifty pounds. This bark, too, was used for making their tents 

 and for troughs, baskets, etc. 



MEDICINAL PROPERTIES. None are known of this species. 



NOTE. The bark of this tree is impervious to water and almost imper- 

 ishable. Fallen trunks are sometimes found with bark in a tolerably 

 good state of preservation, but with wood in the very last stages of decay 

 or even reduced to mould. 



The Indian, when he wished to make a birch-bark canoe, would select 

 a large tree with as smooth bark as he could find, and then make two in- 

 cisions around it, several feet apart, and connect the two with a vertical 

 incision. Then he would carefully peel off the coveted sheet, which 

 perhaps, would measure three or four feet in width and eight or ten in 

 length. Another tree would yield another sheet, and these, while fresh 

 and pliant, he would sew. together with the strong, supple roots of the 

 spruce, and deftly shape them into a beautiful craft. The seams he 

 would smear with pine pitch or resin from the Balm-of-Grilead, and the 

 wales he would reinforce with saplings securely lushed on. A short time 



