76 PRACTICAL FORESTRY. 



multiply this by three thousand, to ascertain that three 

 hundred millions of ties have been used in their con- 

 struction, leaving out of account the thousands of 

 wooden bridges and other structures, in the building of 

 which more or less wood has been consumed. The rail- 

 roads may have assisted very materially in checking the 

 consumption of wood for fuel, but they have probably 

 more than balanced the account in the amount used in 

 their construction, besides the three hundred million of 

 ties must be duplicated every ten years, for the average 

 life of a railroad tie will scarcely exceed a decade, and 

 with nearly all kinds except the best oak, it is a year or 

 two less. 



.The demand for railroad ties is not likely to decrease, 

 but increase, although as timber becomes scarce and 

 prices advance, preserving processes will doubtless be 

 employed to prevent rapid decay. Stone, brick, and 

 iron will also come into more general use for buildings, 

 but the increase in population will also tend to an increase 

 in the demand for other purposes besides that of buildings. 



It is only a little more than a century since coke was 

 first employed for smelting iron ores. The introduction 

 of this fuel to take the place of charcoal, it was thought 

 would save the forests of the world from destruction by 

 the charcoal burners, and while it has done much to- 

 wards making it possible to produce sufficient iron to 

 meet the great and constantly increasing demand, it has 

 not superseded charcoal, and there is probably more 

 charcoal used to-day than at the time coke was first em- 

 ployed in a smelting furnace. Charcoal is still used in 

 furnaces and forges, and there are several establishments 

 in this country that use annually over a million of bushels 

 each, and a score of others that consume from twenty to 

 twenty-five hundred thousand bushels. 



Notwithstanding the number of substitutes that are 

 employed, the demand and consumption of wood appears 



