SELLING LUMBER 



221 



majority of instances, it will very frequently attack the heart- 

 wood. There are some exceptions to this rule, but in the majority 

 of instances the heartwood is not immune when the conditions are 

 favorable. 



The prevention of decay in pine and other classes of lumber 

 has been studied since ancient times. The easiest way to prevent 

 decay is to so use the wood that the necessary conditions for the 

 development and growth of decay-producing fungi are interfered 

 with. A piece of wood which is kept perfectly dry will never 

 decay; that is, a piece of sap pine, if kept perfectly dry, will last 

 twenty years or more. Wood, therefore, which is kept in well 

 ventilated circumstances or under cover, will decay very, very 

 slowly. The same is true for wood which is kept continuously 

 under water. Good examples of this latter are found in the founda- 

 tion timbers of the Swiss lake dwellings, submerged in the waters 

 of Lake Geneva, which are just as sound today as when built by 

 the pre-historic men; also by the foundation piles of the famous 

 Campanile in Venice, which were used practically in their entirety 

 when the Campanile was recently reconstructed. In the ordinary 

 use of lumber much can be done which is now disregarded, simply 

 because people do not pay sufficient attention to simple methods of 

 keeping the lumber away from contact with the soil or in well 

 ventilated conditions. As a good example of this the laying of 

 porch flooring which, when laid tight, is very liable to decay, but 

 which will last a long time if even the smallest cracks are left be- 

 tween the individual boards. 



The most efficient manner for preventing decay is by some 

 process of chemical preservation. The preservation of wood has 

 grown to be a great industry. It has, to be sure, developed largely 

 in connection with timber and lumber used by railroads, steamship 

 companies, and other larger users of wood. In Europe, however, 

 it has for many years been a matter of household application with 

 even the humblest citizen. In 1915 the total amount of lumber, 

 piling, ties, etc., of all woods treated in the United States was 

 equal to about 140 million cubic feet, or approximately 1.7 billion 

 feet board measure. The total number of railroad ties treated 

 equaled 37,085,585, of which 8,541,203, or 23.03 per cent, were 

 yellow pine; 3,817,929 lineal feet of piling were treated at Gulf 

 Coast plants, and 3,134,993 lineal feet were treated in Atlantic 

 Coast plants, probably most of which was Southern yellow pine. 

 The total amount of paving blocks treated in 1915 equaled 2,936,- 



Wood Con- 

 tinuously 

 Wet or Con- 

 tinuously Dry 

 Does Not 

 Decay 



Prevention 

 of Decay 

 by Chemical 

 Treatment 



