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FOXWORTHY. 
Gardner, E. Mechanical Tests of Thirty 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- 
Petrucci, and these two works constitute the best contribution to our 
knowledge of the woods of Borneo. 
Besides these there have been a number of individual articles on par- 
ticular woods: but there has been very little done in the way of com- 
parative study of the woods of the whole region. 
II. PROPERTIES OF WOOD. 
COMPARISON OF WOODS OF THE TROPICS WITH THOSE OF TEMPERATE REGIONS. 
In general, tropical 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 AND HARDNESS. 
These two qualities usually go together ; but the weight can not be 
considered as an accurate measure of hardness. It is usually true that 
a very heavy wood is also very hard; but 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 one table. 
Weight . — The weight of a given wood is due to the density of the 
walls of the different 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 sapwood 
and heartwood indiscriminately, and to the fact that some workers have 
not used 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 studies. 
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 of 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 use only four classes, as outlined by Gardner and 
