278 TIMBER 



diversity of opinion as to its advantages, and it is much 

 more suitable in some situations than in others. 1 



Boucherie's Process, which appears to be the same as 

 Marjery's, consists of the injection of sulphate of copper in 

 the proportion of 1 Ib. of copper to 8 or 12 gallons of 

 water, and was at one time used with fair success in 

 England for telegraph poles and is now used in France 

 and Germany ; in the latter country posts have a life of 

 over thirteen years. According to a recent statement in 

 L' Electrician,, Paris, vol. 32 (1906), it is necessary that the 

 wood should be treated not later than eight or ten days 

 after the tree is cut down, and another disadvantage is that 

 the life of the posts is affected by the nature of the soil in 

 which they are placed. 



Kyanizing is the impregnation of timber with bichloride 

 of mercury in the proportion of 1 Ib. of the bichloride to 

 5 gallons (about 50 Ibs.) of water ; it is sometimes simply 

 allowed to soak into the wood steeped in the vat, but as a 

 rule it is pressed in- the same way as in the case of bur- 

 nettizing and creosoting, and in the same tanks which are 

 used for creosoting. 



Kyanizing is much used by the North Eastern Bail way 

 Company in Newcastle-on-Tyne and district for the treat- 

 ment of wood for coaling staiths, planking of bridges, etc., 

 and for the latter it has proved very satisfactory. The 

 author has a specimen of kyanized plank cut from a bridge 

 deck after being in an exposed situation for forty-one 

 years, which is perfectly hard and sound. The process is 

 said to be a preservative against fire, but that is very 

 doubtful, and in water, particularly sea water, it appears 



1 Latest practice aims at getting not less than half a pound of pure 

 zinc chloride into each cubic foot of timber. 



