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The Q. ped. is that species of timber which is used for park palings, 

 laths, &c., on account of its splitting so readily, and if any one will take the 

 trouble to examine park paling he will find that it is invariably wedge-shaped ; 

 the lines of cleavage radiating from the centre to the circumference of the 

 tier, along the course of the principal medullary rays peculiar to the Q. ped. 

 When we see split oak timber in the shape of laths or poles, we may put it 

 down at once as of this species. The Q. sess. refuses to split in this manner 

 at all; it is more homogeneous, having no principal river of cleavage, 

 because it has no principal meduUary rays ; when it splits at all it splits 

 irregularly. Again, this easily split wood of the ped. is also more easily 

 broken across than the other, and on examining the fracture it will be found 

 to occur just where the medullary rays have been severed in shaping the 

 plank. In short, this species is comparatively brittle, and the sess. is the 

 tougher of the two. It is true the wood of the ped. is harder than that of the 

 other, and more diflScult to work, but hardness in wood is no test of strength ; 

 in fact, the hardest woods are usually the most brittle. Hardness in wood 

 generally accompanies slow growth, and the Q. ped. is much slower in growth 

 than the sess. But now mark the results of Professor Barlow's experiments 

 at "Woolwich on the comparative strength of slow and fast grown oak of the 

 same species. The fast grown was deflected one fiftieth of its length, with a 

 weight of 606 lbs., and broken with 999 lbs. ; while the slow grown was 

 deflected by 439 lbs., and broken by 943 lbs., showing that the fast grown was 

 superior to the other in the proportion of 15 to 14 nearly. These speci- 

 mens, experimented upon, were, as I have said, of the same species, the 

 ped. ; but the experiment is of some value, as showing the great probability 

 of the superior strength of the faster growing species, the sessUiflora. 



That the sess. is by a great deal the faster growing tree of the two no one 

 can doubt who has ever examined many specimens. There can be no question 

 about it, and from these twigs (exhibited), which are fair average specimens 

 of the two trees you can readily judge for yourselves. The sessU. is distin- 

 guished by its larger, glossy leaves, and its more luxuriant shoots. 



And now with regard to durability. The evidence of durability of the 

 Q. pedunc. is negative, and this is somewhat remarkable ; there is no 

 evidence at all of great durability, at least I have not been able to meet with 

 any — by great durability I mean 300 or 400 years— and I think this is remark- 

 able, because the advocates for the Q. peduuc. being the superior wood would 

 naturally have furnished us with examples of this durability if such examples 

 were to be found. I do not say that it is not durable, but only that there 

 is no existing proof of its being so. 



On the other hand, the great durability of the sess. oak is unquestionable. 

 It was formerly supposed that the timber used in the fine roof of St. Alban's 

 Abbey, Westminster-hall, and many noble timber roofs in London, was 

 chestnut ; it is now known for certain that it is sess. oak. The mistake arose 

 from its going among carpenters and others by the name of chestnut oak, from 



