5 
The following is an extract from the Tropical Agriculturist of Ceylon:— 
. . . . But we were greatly interested in a stable door composed of fine planks of a Grevillea 
tree, certainly not more than sixteen years old (if that), which had been cut down and converted into 
timber. Made into the door when freshly sawn, this valuable wood had subsequently seasoned without 
in the least warping. Such being his experience we were not surprised to learn that the owner intended 
to cut down some of the older Grevillea trees which can be spared from the large number at Lome, to 
be converted into floor boards. 
Exudations. —Tor an account of a gum-resin from this well-known tree see 
Eleury.* Maidenf shows that the silky oak belongs to the small list of trees that 
exude both a gum and a resin. Lauterert also gives an account of the resin. A 
research on the interesting exudation from this well-known species is a desideratum. 
The substance was exhibited in the New South Wales Court, Paris Exhibition, 
1867. 
The following are some notes on the exudation by Mr. W. Baeuerlen, who collected 
it for me on the northern rivers :—“ When quite fresh and soft it is of a peculiar 
yellow colour, but on hardening it assumes something of a flesh or wine colour. 
It has an extremely disagreeable smell. . . . The local opinion is that there is 
more gum during very rainy weather than during drier times. The country people 
look upon it as a nuisance, as it sticks to the horses’ manes when they rub them¬ 
selves against the tree.” 
A few years ago a Sydney timber merchant sent to me a quantity of material 
which “looked like whiting,” and which was found in the middle of a log of silky 
oak he was cutting up. Earthy-looking deposits in timber are rare, hence it was 
subjected to chemical examination^ Mr. Smith continued the research|| by 
examining the sap, collected as fresh as it was possible to obtain it, logs being cut 
into short lengths and allowed to drain into a receptacle. He detected butyric acid 
in the sap, which substance does not appear to have been previously found in the 
sap of any tree. The succinic acid contained in the solid substance described in the 
former paper was probably derived from the natural oxidation of butyric acid. 
Mr. Ft. I). Hay informs me that in the Dorrigo the Carabeen ( Sloanea 
Woollsii , E.v.M.) is disliked by the sawmillers, because of a deposit (locally known 
as “ flint ”) in the log, near the heart, which injures the saw. This deposit resembles 
lime in appearance, is clipped bv a knife with difficulty, and has not yet been 
subjected to chemical analysis. 
w Fleury, G.—“ Grevillearohusta gum-resin.” Journ. Pharm. (5) ix, 479. Journ. Chem. Soc., xlviii, 23S. Investi¬ 
gation of a gum-resin found on some trees of Grevillea rohusta in Algeria. 
t Maiden, J. H.—“ Gums and a resin produced by Australian Proteaceie.” Proc. B.S., S.A., 1S89, page 54. 
$ Lauterer, J.—“Gums and resins exuded by Queensland plants chemically and technologically described.” From 
pages 35 to 80 of F. M. Bailey, Botany Bulletin, No. xiii (April, 1896), “ Contributions to the Queensland Flora.” 
§ Maiden, J. H., and Smith, H. G.—“On a natural deposit of Aluminium Succinate in the timber of Grevillea 
rohusta, R.Br. Proc. Boy. Soc., N.S. W., 1895, page 325. 
|| Smith, H. G.—“ On the constituents of the sap of tho Silky Oak,” Grevillea rohusta, R.Br., and the presence of 
butyric acid therein. Ib. 1896, 194, 
