02 PROPERTIES OF WOOD. 



in rivers involves a partial absorption of these salts from the 

 sapwood by the water, so that the weight of the wood is 

 reduced. Wood-merchants say that this loss is slight, but 

 detailed investigation is wanting. It is evident that injection 

 with preservative substances must increase the weight of wood. 

 Still less investigated is the share of ash- constituents in 

 the weight of wood, but at any rate it is inconsiderable. In 

 broadleaved and coniferous wood, as soon as the annual zone 

 is completed, there is no further addition of ash-constituents.* 

 In palms and bamboos, the wood of which is intermediate to 

 exogenous wood and bark, there is a change in the mineral 

 constituents during the whole life of the stem. Thus the 

 quantity of silica steadily increases, so that the sp. weight 

 is considerably increased. According to Koide, the sp. 

 weight of the Hachiku bamboo (Pliyllostachys pnberida) is in 

 the first year 109, in the fifth year 113, in the eighth 118, 

 but after the eighth year it steadily diminishes with the age 

 of the bamboo. This law is true for all bamboos, f 



A knowledge of the sp. weights of forest-dry wood is of 

 ractical importance as regards transport from forests. It is, 

 however, very variable. Bohmerle and Vultejus have deter- 

 mined these weights as follows in kilograms per cubic meter, 

 solid or stacked, and they are also given in pounds avoirdupois 

 per cubic foot. 



OAK, BEECH, 1 HORNBEAM,- ASH, SYCAMORE, ELM. 



The weights of beech and hornbeam cordwood are given in the 

 second column in metric and English weights and measures. 



Kilo*. Lbs. 



(Cubic meter) Logs 720... 



(Stacked cubic meter) Split cordwood ... 670 ... 840 1 

 Hound ... 600 ... 820 2 



Stump ,, ... 614 ... 

 100 faggots 1,200 ... 



. 45-3 per cubic foot. 



. 42. ..53 1 



. 38. ..50-52 



. 38-5 



. 75-5 per 100. 



* [Masses of opaline silica termed tdbanhir are sometimes formed in the 

 hollows of bamboos, while the vessels of Arm-in (\dcclin ;md of teak may bo 

 filled with calcium carbonate and calcium phosphate or silica. In A. Catecltn 

 this property renders the wood better for catch-making. Tr.] 



f [This fact has long been known in India, where bamboos have a consider- 

 able commercial value. The culms up to a certain age vary in external colour 

 and increase in weight ; only the heavier ones a re used for building purposes, while 

 after attaining a maximum density they gradually rnl. Their age is known by 

 the colour of thnr rind. Tr.J 



