Having performed an analysis of the cially hard tropical woods of superial quality described hereafter by employing the Schorger's method, we found that they have marked characteristics if compared with those of hard woods grown in the temperate zone.
1. Rose wood, Dalbergia cochinchinensis Pierre.
2. Rose wood, Darbergia sp.
3. Ebony wood. Diospyros mollis Griff.
4. Iron wood, Cassia siamea Lamb.
5. Pradu wood, Pterocarpus indicus Willd.
In the first place, it must be pointed out that these woods contain a large quantity of soluble matters, that means, ca 24% of hot water extract, ca 12% of ether extract, and ca 43% of 1% NaOH extract. Almost the half of the hot water extract consists of tannin and sugars, but the remainder is quite unknown.
In the second place, it has been found out that they contain a remarkable quantity of β cellulose surpassing two times of γ cellulose.
In the third place, it will be worthy of note that the iron wood contains 0, 17% of mannan; this finding shows an exception to the hard wood, but a resemblance with the coniferous wood.
Finally, we should like to emphasize that the woods mentioned above, excepting ebony wood, contain neither mannan nor galactan as in the case of monocotyled on viz. palm and bamboo (I. Miura, and T. Honda, Chemistry of Wood, part 2, Bulletin of Tokyo Imperial University Forest No.15).

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