CONVERSION AND SEASONING 



67 



ancient Egyptian objects in the Britisk Mnseum must be several 

 thousand years ; wood of Juniperus Oxycedrus buried in the island 

 of Madeira has remained undecayed and fragrant for 400 years ; 

 and Spruces 3 to 4 feet in diameter have been observed in the moist 

 forests of North- West America growing on the prostrate but still 

 sound trunks of TJiuya gigdntea. 

 Speaking at the Surveyors' Institution in 1905, Mr. H. J. Elwes 



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Fig, 40. — A beam, showing structural aggregates. 1, centra-l or pith cone ; 

 2, cyhnder of rings contmuous throughout; 3 and 4, partial cylinders, making 

 "bastard faces " on the sides. (Modiiied from Roth.) 



said : " Last April he was in a house in Massachusetts which was 

 built of White Oak in 1704, and had never paint or tar or preser- 

 vative on it, and yet stood sound and water-tight to-day. He had 

 hved in Switzerland in a house built of Larch logs which dated 

 back more than 400 years. He had also Hved in a timber house in 

 Norway said to be 160 years old, and still perfectly sound, although 

 the much-despised Spruce was the timber used." 



Seasoning.!— By girdling standing timber the process of season- 





FiG. 41.~Plaiik well laid, with mside, or inner rings, downward. (After Laslett.) 



ing is to a great extent anticipated. Thus, in order to float the 

 timber, which in its green state is at least as heavy as water, it is 

 the general practice in Burmah to cut a complete ring through the 



^ " There is probably no one to-day who does not believe that timber preservation 

 in one form or another pays. Treated timber in almost every respect is cheaper in the 

 long rmi than untreated timber ; furthermore, the better treatments, although more 

 expensive at first, are much cheaper in the long run. "—Hermann von Schrenk (1905). 



6—2 



