THE BO'NESS PIT-WOOD TRADE. 11 



For long pit- wood of 3 incli top-diameter, running from 10 feet 

 to 35 feet in length (average 15 feet to 16 feet), the price per 100 

 linear feet is now 4s. 6d. 



The rates above quoted represent from 5^d. to 5|d. per cubic 

 foot "ex ship," to which rate must be added from ^d. to fd. per 

 cubic foot for shore dues, loading, and depot expenses, bringing 

 the cost to purchasers at the port up to from 5|d. to 6|d. per 

 cubic foot. Railway freight to the mines forms, of course, an 

 additional charge. 



The Transactions of the Mining Institute of Scotland, vol. xx., 

 part 2, 1898, contains an interesting paper by Mr George L. Kerr 

 on " Timbering and Supporting Underground Workings." As 

 regards the species of wood used, the author says : "The different 

 kinds of wood used for mine-timbering in Great Britain are larch, 

 Scotch fir, Norwegian pine, and sometimes oak and beech. In 

 ordinary timbering Scotch fir is largely used, especially where 

 the timber does not require to be heavy, and where the pressure 

 is not great ; but in drawing and main roads that have to be kept 

 open for some time, larch has been found to be moat efficient, both 

 as regards durability and economy. Any woods that are long- 

 grained and elastic, and will yield to thrust, are suitable for mine- 

 timber, because props of such woods often serve the purpose for 

 which they are used, even when partially fractured. Beech or oak 

 props are short-grained, more or less brittle, and break off short 

 under crushing strain. Their great weight, as compared with 

 other woods, and the consequent difficulty in handling them, is 

 against their use underground." He states that the cost of 

 timber per ton of coal raised varies in different districts and dif- 

 ferent collieries from |d. to 9d., according to the depth from the 

 surface, the thickness of the seam, the nature of the roof, the 

 inclination of the seam, and the method of working. He gives 

 the crushing strain for ordinary larch props as H to 2 tons per 

 square inch, " according to the age of the wood and the seasoning 

 that it has undergone." If the timber be cut when green, and 

 allowed to season or dry in a gradual manner, it is said to be 

 49 per cent, stronger than "ordinary pit-props." The writer con- 

 cludes his paper with the following remarks on the preservation 

 of timber: — "Timber required for use underground, or indeed 

 anywhere, should be cut in winter, when the wood has little sap 

 in it, because the sap ferments and causes rapid decay ; wood 

 should also be well seasoned before being used ; and if these two 



