2lf^S 



Forestry Exhibition at Norwicli, 1911 



It should be noted that the amount taken up by timber 

 appears to depend mainly on : — 



(1) The species. 



(2) The age of the timber and extent to which visible 

 heartwood has developed. 



(3) The structure and texture of the timber, e.g. whether the 

 wood consists mainly of thick walled or thin walled elements. 



(4) The amount of water present in the timber. 



(5) The exact composition of the creosote oil and the 

 method of its application to the timber. 



Some species absorb creosote more readily than others. 

 Young, rapidly-grown, coniferous timber with slight heart- 

 wood development will take up far more than matured timber 

 with well developed heartwood. Timber grown in open 

 stands will absorb far more creosote than the close even- 

 grained material taken from close forest. 



The practical question is, how much creosote is really 

 required to effect the object in view ? The answer would 

 appear to depend largely on the extent to which creosote 

 acts as a germicide and the extent to which it acts as a water- 

 proofing material. Space does not permit of this question being 

 discussed in detail, but it may be noted that it is quite possible 

 to make the process too costly and that more creosote may easily 

 be injected into the timber than is absolutely necessary. 



The following extract from a table of figures relating to 

 the above, prepared for the Earl of Leicester by Mr. Donald 

 Munro, may be of interest : 



Extract from table showing the quantity of creosote absorbed 

 by different kinds of home-groion air-dried timber under 

 90 lb. pressure for 3 hours, each piece of timber being equal 

 to I" cubic foot. Price of creosote, 4|(i. per gallon ; sp. gr. 

 1-060. 



