322 TIMBER AND TIMBER TREES. [CHAP. 



carbonising timber by means of inflammable gas (either 

 pure hydrogen, or, better still, lighting gas) directed 

 by means of a tube against every part to be carbonised, 

 just as one would direct a jet of water from a fire- 

 engine upon the flame to be extinguished. A trial of it 

 was made at Cherbourg in presence of the Director of 

 Naval Works and numerous other witnesses, and it is 

 said this was crowned with complete success. The 

 absence of all danger from fire was clearly proved, 

 and this of course x removed the principal objection 

 to its introduction in the dockyards. The cost, it 

 appeared from calculations made at the gas-meter 

 of the town, with the aid of an accountant, did not 

 exceed one penny per square metre for gas and labour 

 together. 



M. de Lapparent holds that, the surface being once 

 thoroughly dried, the juices of the interior will remain 

 inactive, and the durability of the timber be thereby 

 insured. 



I experimented with this process at Woolwich in 

 1862, by charring seven out of twelve pieces of winter- 

 felled British Oak, prepared to a scantling of 2" x 2" x 

 84" and disposed of them as follows : for instance, 

 Nos. 3, 7, 8, 9, 10, n, and 12 were carbonised, and Nos. 

 I, 2, 4, 5, and 6 were not carbonised. Of the former, 

 Nos. 3 and 10, and of the latter, Nos. I and 2, were 

 suspended in a dry place in the store room ; Nos. 7, 8, 

 and 9, and Nos. 4, 5, and 6, were put into a box of 

 manure; Nos. n and 12 were driven half their length 

 into damp earth, on the stacking ground. 



