50 



the limits which I am forced to prescribe to myself in the discussion of the subject, will 

 not allow me to treat of them except in a general manner. 1 shall therefore, confine my 

 remarks chiefly to the oak, because from its more extensive application in subservience to the 

 the wants of social beings, it holds the most important rank among them. I shall, neverthe- 

 less, refer to such other trees as may be pertinent to the occasion. 



The family of oaks is very numerous, amounting to somewhere about one hundred and 

 forty species. Few of them have, however, been found profitably available for building 

 purposes, or generally in rural economy ; the number, nevertheless, may be considerably 

 increased, if needed, by the appUcation of the means indicated by science, to which a more 

 particular reference will be had in the sequel. 



Of the white oak, {Qiicrcus alba,) with which I shall commence, though a volume might 

 be profitably written, little at this time need be said, because its character or properties are gene- 

 rally well understood. Deprived of its alburnum or sappy portion, well seasoned before use 

 and kept in a dry atmosphere, it is for general purposes of building the most valuable of 

 any other hitherto known. 



This tree frequently grows in forests to the height of one hundred and twenty or thirty 

 feet ; but in openings it spreads into branches and seldom attains more than one half or two-thirds 

 that elevation. The girth at the felling point varies according to soil, frequently exceeding 

 twelve and even fifteen feet. It is of great value, particularly in ship building. 



There is, however, a veiy material difference in the quality of oak timber — that for instance 

 prepared from trees which grow in openings, or isolated measurably from all other trees, is 

 more compact in its organic structure, stronger and more durable than that taken from dense 

 forests. Again, those which grow in an atmosphere charged generally with sea water, or in a 

 soil slightly impregnated with the chlorate of soda and which, consequently, contains salts of 

 that material, are far less perishable tlian those produced under different circumstances, and which 

 assimilate the salts of potash instead of those of soda. These qualities are again modified 

 by the conditions of the producing soil ; if dry, or somewhat elevated, the growth will be much 

 slower than in low, moist lands, and, consequently, they will be more valuable or durable. 



These remarks respecting the character or properties of the white oak apply also to the 

 chestnut tree, {Castanea Americana,) — and are facts well known to our experienced ship-builders 

 — and I have no doubt they will, with equal propriety to most other timber trees similarly 

 circumstanced. 



