412 FOX WORTHY. 



Gardner, R. Mechanical Tests ofThirty Different Philippine Woods. 

 For. Bur. (Philip.) Bull. 4 (1907). 



Beccari, 0. Nelle foreste di Borneo. Florence, 1902. In this work, 

 Doctor Beccari gave brief notes on the nature and uses of many of 

 the woods of Sarawak. Detailed structural notes on these woods collected 

 by Doctor Beccari were published In Malpighia by Dr. G. Bargagli- 

 lVtrucei. and these two works constitute the hest contribution to our 

 knowledge of the woods of Borneo. 



Besides these there have been a number of individual articles on par- 

 ticular woods: hut there has been very little done in the way of com- 

 parative studv of the woods of the whole region. 



II. PROPERTIES OF WOOD. 



comiwkisox or wooes of THE TROPICS with THOSE of tkmi'K.katk BKGION8. 



In general, tropica] woods contain more of color than do those of 

 temperate regions. Cognate with this is the fact of their greater weight 

 and hardness. Distinct seasonal growth with the formation of definite 

 rings of seasonal growth is much less common in the tropics than in the 

 temperate regions. 



WEIGHT AM) UARhNESS. 



These two qualities usually go together; hut the weight can not he 

 considered as an accurate measure of hardness. It is usually true that 

 a very heavy wood is also very hard: hut this is not always the case. 

 Occasionally, also, a wood which is only moderately heavy will prove to 

 be very hard; consequently, it is not possible to combine these two qual- 

 ities in on*; table. 



Weight. — The weigh! of a given wood is due to the density of the 

 walls of the differenl elements together with the nature of the contained 

 deposits and the closeness of crowding together of the elements. 



In published statements of weight, there is a considerable factor of 

 error due to natural variability in density, carelessness in using Bapwood 

 and heartwood indiscriminately, and to the fact that some workers have 

 not u^vd carefully dried wood. It is perfectly plain that any measure- 

 ment of a moisture-containing wood which does not indicate the percent- 

 age of contained moisture is a source of confusion in comparative studio-. 

 Unfortunately, some workers have published weights of "air-dry" wood 

 without indicating what percentage of moisture was meant. 



In the following table only a rough comparison has been possible among 

 the most used woods of this part of the world. Wherever possible. Large 



numbers of samples <»f a given wood have been tested. In many cases 



this has not been possible and it has been necessary to rely on the work 



Of others or on comparative estimates made by traders and timber workers. 



It has seemed best to \[>v only four classes, as outlined by Gardner and 



