Wood Preservation 



spikes and nails driven into timbers treated. They remain tight 

 whatever happens. Creosote can be thoroughly appHed with 

 moderate cheapness. It can be had in large quantities from gas 

 works. The average tie of white oak costs sixty cents and thirty 

 cents to lay it. Creosoting costs but twenty cents additional. 

 Treated ties are still sound after untreated ones have been replaced 

 several times. 



A very fortunate coincidence was discovered in the course 

 of the investigations on wood preservation. Hard woods, like 

 white oak and longleaf pine, do not absorb preservatives as 

 rapidly nor as thoroughly as cheaper, more porous woods, with 

 thicker sap wood, like red oak and Cuban pine. Therefore, the 

 cheap woods, well saturated, outlive the dear ones. White oak, 

 for which railroads oflFer fifty cents a tie, will bring double that 

 sum at the furniture factory. Railroads cannot longer afford 

 to use white oak. Beech, properly impregnated, will outlast 

 white oak. Its normal life of five years can be extended to 

 twenty-five years. 



The Bureau of Forestry, with the co-operation of railroad 

 corporations in different sections of the country, has elaborate 

 experiments in progress bearing upon the preservation of wood. 

 The work is disinterested and scientific, and creosoting is the 

 method that has proved best. The important railroad systems 

 of England and the Continent have reached the same conclusion. 

 Creosoting ties is there as much a matter of course as laying them. 

 The higher prices and greater scarcity of timber in Europe ex- 

 plain why they are so far in advance of us in the practice of wood 

 preservation. 



The importance of thoroughly seasoning wood before im- 

 pregnating it with chemicals cannot be over-estimated. Green 

 wood, full of sap, resists the entrance of any substance, especially 

 oils. Even if this difficulty could be surmounted, the seasoning 

 of wood produces cracks through which decay gets in, and im- 

 pregnation counts for naught. Before treating, railroad ties are 

 bored with holes for the entrance of the spikes, so that even 

 these small apertures oflFer no untreated surfaces for water 

 containing disease spores to enter. 



Creosoting paving blocks, piles for bridges, wharves and 

 cribs and the exposed hulls of wooden vessels is successfully 

 and extensively done nowadays. The ship worm does not 



