THE OAK 7 
for shipbuilding, these same acorns, now despised 
by the advanced agriculturist, constituted the chief 
value of the Oak. Thus in the Domesday Survey 
the woodlands are estimated at the number of 
swine for which their acorns and masts afforded 
“ pannage,” 
Whatever may be the extension of the use of 
iron, Oak timber will always be of peculiar value 
for many purposes, though that important bye- 
product, the bark, is of sufficient consequence con- 
siderably to influence the English forester’s treat- 
ment of his woods. There is more tannin in the 
bark in spring, when the sap is rising, than at 
any other season, and it is, therefore, the common 
practice to fell the trees at that season instead 
of in winter, though for timber only it is admit- 
tedly preferable to fell in the latter period. 
The most expert judges cannot separate the 
woods of the two best varieties. Few woods are so 
durable under all circumstances, few so generally 
useful. “Oak,” says Professor Marshall Ward, “is 
neither the hardest and heaviest, nor the most, 
supple and toughest of woods, but it combines in 
a useful manner the average of these qualities.” 
The broad, lustrous, light-coloured pith-rays, and 
the pore-circle of large vessels in the spring wood 
are the most striking features of Oak wood when 
magnified. Even the crooked branches are valuable 
in boat-building; but the familiar inky stains round 
the nails of many a park-fence show that the 
tannic acid in the wood is detrimental to iron, 
converting it, in fact, into ink, as it does in the 
