224: WOODS OF COMMERCE 



drcle of very large vessels ia the spring-wood, which is only a single 

 row when the rings are narrow, or four rows when they are wide. 

 Into the autumn-wood there radiate outwards straight or bifurcating 

 bands of finer vessels, tracheids, and cells. Numerous, very 

 narrow, wavy, peripheral lines (" false rings ") of wood-parenchyma, 

 recognizable by their contents, but seldom more than a single row 

 of elements each, are generally visible, especially when the annual 

 rings are broad. 



Owing to the large proportion that the pores bear to the fibre 

 when the annual rings are narrow, such slow-growing unthrifty 

 Oak, growing on poor soil or in severe chmatic conditions, is, 

 though often beautifully marked, softer than the broad-ringed, 

 thrifty, quick-grown wood of good soils and a favourable climate. 

 They may differ to the extent of their specific gravities— a fair 

 criterion of their hardness and strength— varying fropa 691 to 827 

 respectively. 



Querms Robur is a somewhat variable species, three somewhat 

 inconstant tjrpes being recognized as British — viz., pedunculdta, 

 sessiflora, and intermedia, Q. Bobur pedunculdta derives its 

 scientific name from the long stalks to its acorns, for which reason 

 a;lso the Germans call it " Stieleiche," whilst from the situations 

 in which it grows they call it "valley Oak" (Thaleiche), and 

 from its early production and shedding of its leaves it is called 

 *' Early Oak " (Friiheiche) and " Sommereiche." It is generally 

 quick-growing, but does not, perhaps, produce so great a length of 

 clear stem as sessiflora. Its wood may be lighter in colour, whence, 

 apparently, it gets its French name, " Chfene blanc "; but it is 

 generally more compact, denser, and tougher, and therefore better 

 for purposes where strength is a primary consideration. 



Q. Robur sessiliflora, known, from a supposedly greater resemblance 

 in its wood, as " Chestnut Oak," by the French as " ChSne rouge," 

 and by the Germans as " Traubeneiche " " Red (Rotheiche), Hill 

 {Bergeiche), Late " (Spateiche), or *' Winter Oak," has long stalks 

 to its leaves, but not to its acorns, and is apparently generally less 

 dense in its timber. It is also, perhaps, more hable to shakes ; 

 but it must be admitted that, in the absence of any record as to 

 the source of the logs or of any exact measurement of specific 

 gravity, timber-dealers cannot discriminate the wood of these two 

 varieties. Stunted specimens, grown on rocky hill-sides, produce 

 crooked, hard, knotty wood, difficult to spHt, formerly of consider- 

 able value in ship-building ; and Coppice Oak is of a similar char- 

 acter. 



Q. Robur intermedia, the Durmast Oak, is not common. It has 

 short stalks to both leaves and acorns, and its leaves are downy 

 on their under-surfaces. It has a broad sapwood and a dark-brown 

 heart, and is considered of inferior quality. 



