OAIi 22a 



certain districts ; and, though it can be readily seasoned, it is very 

 liable to warp and shrink during the process. 



When Oak was largely in use in our royal dockyards the rules 

 as to specifications were that only logs would be accepted 10 ft. 

 or more in length that would side 9 in. and upwards in proportion 

 to their length ; and that each piece was measured for contents 

 by calliper measurement as far as its spire (or top-end) " will hold 

 12 in. in diameter." Thirty inches calliper will yield sided timber of 

 about 21 in., 24 in. calliper 18| in the side, or on an average a 

 '' siding " of about seven-tenths of the calliper measurement, or 

 more precisely 70 in. from 99. For fencing or staves Oak splits 

 easily, with a moderately smooth surface ; and, for ornamental 

 purposes, it is susceptible of a high polish. 



The sapwood is very liable to insect attack, and cannot be termed 

 durable ; 'but the heart, whether under ground, under water, or 

 exposed to alternations of drought and damp, is remarkably so, 

 few woods changing so little when once seasoned. The " life ^' 

 of a railway-sleeper of young Oak is stated to be from seven to ten 

 years if not treated with any preservative, or sixteen years if treated 

 with zinc chloride. The piles of Old London Bridge, taken up in 

 1827, sound after six and a half centuries' use, are a striking instance 

 of these lasting quahties ; whilst the " Bog-oak " blackened by the 

 action of the iron salts in peat-mosses on the tannin it contains — 

 a natural ink — ^remains sound after far longer periods. The 

 durability of Oak timber is undoubtedly affected by the time of 

 year at which it is felled, the best season being winter, when there 

 is least water and sap or fermentable matter in the wood. The 

 greater amount of tannin in the bark and the greater ease in stripping 

 it in the spring have, however, often led to the trees being felled at 

 that time. Incipient decay often shows itself in the heartwood 

 of ancient Oak-trees as ''foxiness," a warm deepening of the colour 

 that actually enhances the value of the wood for some ornamental 

 purposes. It is then known as Brown Oak, and is often cut into 

 veneers, sometimes fetching very high prices for this purpose. 

 A tree felled at Welbeck, for instance, realized £100, and one from 

 Lord Pitzwilliam's seat, Wentworth Woodhouse, £110 ; while 

 six at Burghley House averaged £75 apiece. 



The minute structure of Oak has already been to some extent 

 described and fully illustrated in Part I. The pith, at first white, 

 then brown, is pentangular, and from 1 — 4 milHmetres across : 

 the pith-rays are of two kinds, very broad, lustrous, light-coloured 

 ones— the ''silver-grain" — sometimes f in. apart, and others, 

 far more numerous — about 300 to the inch — very fine and less 

 straight. The annual rings undulate slightly, bending outwards 

 between the broad pith-rays : they vary in width from 1 — 8 or 

 more millimetres, and they are conspicuous owing to the pore- 



