CHAP. XLI. LEGUMINA‘CEE. ROBI NIA. 619 
ever different the results, it may safely be concluded, that sound acacia wood 
is heavier, harder, stronger, more rigid, more elastic, and tougher, than that 
of the best English oak ; and, consequently, that it is more fit than oak for 
trenails. The late Lord King, who had some large locust trees on his 
estate at Ockham Court, gives the following opinion of the strength and 
durability of the timber. Te says, “ It endures as posts longer than oak or 
any other wood, except yew ; but it is not as well known that it never breaks 
to any strain: I can give you an instance in proof of this. We are in the 
habit of using a machine called, with us, the /oisters, for bringing home 
large trees without any other tackle. The axletree is always made of the 
best ash; and yet mine never lasted more than two years, without being 
broken with the strain of lifting trees from the ground, occasioned by the 
sudden force when the pole turns over. About 25 years ago, my carpenter 
put in an acacia axle, which lasted 11 years, and then was as sound as it was 
the first day ; but, as the wheels were worn out, the carpenter thought it best 
to put in another acacia axle, as some of the pin-holes were a little worn; and I 
believe that axletree now remains in use.” ( Withers’s Treatise, p. 283.) At 
Goodwood, in Sussex, there are a great many acacia trees in the plantations, 
which were planted in the days of Collinson and Miller. The timber has been 
chiefly used for out-door fences ; and, after standing 30 years, is yet perfectly 
sound. It is there considered much superior to the oak, for its strength 
and durability. (Jbid., p. 290.) | At Cheam, in Surrey, on the estate of A. 
Palmer, Esq., there are acacia posts which have stood 30 years, and are 
quite sound ; and trees which, after having been 14 years planted, are large 
enough for making such posts. (Jéid., p. 289.) In the various communi- 
cations to Mr. Withers, there is no evidence of the durability of the locust 
as hop-poles, notwithstanding all that Cobbett has said on the subject. One 
writer speaks of trying the young trees in that capacity; and another says 
that he found that the locust, when about the size of a stake, did not 
possess more durability than stakes of the oak or the beech, of the same di- 
mensions. The sap-wood of the acacia, this writer adds, appears to be 
equally as rapid in decay.as that of the oak. (Jbid., p. 249.) The truth is, 
as Lord King and Lord Stanhope observe to Mr. Withers (Zéid., 591. and 
292.), the acacia is a branchy-headed tree, both when young and old; and is 
neither calculated to produce straight poles in the former state, nor much 
timber in the latter. : 
In America, according to Michaux, the greatest consumption of locust 
wood is for posts; which, if the tree is felled in winter, when the cir- 
culation of the sap is suspended, and the posts are allowed to become 
~perfectly dry before they are set, are estimated to last 40 years. This dura- 
tion, however, varies exceedingly, according to the soil and situation in which 
the trees have grown; those having the heart-wood red lasting twice as long 
as those in which it is white. Michaux has remarked that, if the trunks of 
the locust trees grown in the north of Pennsylvania exceed 15 in. in diameter, 
when they are cut down and split open, they are frequently found to be de- 
eayed at the heart; but that this is not the case with trees that have grown 
farther south: which shows that poor soil and a cold climate are not suf- 
ficient, as Governor Pownall seems to allege (see p. 615.), to make the tree 
produce good timber. The American shipwrights use as much locust 
wood as they can procure; finding it as durable as the live oak, and 
the red cedar; with the advantage of being stronger than the former, 
and lighter than the latter. It is difficult, however, to procure locust 
wood of sufficient size for ship-building ; for, even in those districts where 
the tree thrives best, nine tenths of the trunks do not exceed 1 ft. in di- 
ameter, and from 30 ft. to 40 ft. in height. The wood is used for trenails in 
all the seaports of the middle states, to the exclusion of every other kind of 
timber. Instead of decaying, it acquires an extraordinary degree of hardness 
with time. In 1819, these trenails were 10 dollars athousand at Philadelphia ; 
and from 50,000 to 100,000 of them were annually exported to England. 
