364 
IV. >l'c; u>r Warren gives the weight of some Swamp Mahogany at 75-98 Ib. per 
cubic foot; the same specimen weighed three years later gave 61-6 Ib. per cubic foot. 
Baron vo:i Mueller and Mr. Hummel give the specific gravity of " air-dried wood " 
at 03-15 1!).. and " absolutely dry " at 56-45 Ib. per cubic foot. A specimen of Swamp 
Mahogany weighed by me after having been cut nearly thirty years gave a weight of 
58-6 Ib. per cubic foot. I do not attach too much importance to these figures, as to be 
comparable, the timbers should have been obtained from trees grown under similar 
circumstances, of about the same age, and taken from the same part of the tree. It 
would be a useful work to be undertaken by a Government department or some 
wealthy individual this determination of the specific gravities of our timbers. It 
would occupy the unremitting attention of one observer for several years to do it 
properly. Meantime, we must be content With specific gravity determinations, of 
the relation of which to each other we know little or nothing. 
It is so durable that the late Father Scortechini (Proc. Linnean 8oc. N.3.W. 
vii, 248 (1883) goes so far as to say that its timber is reported immune from borers. 
It is being planted in Chili, and is appreciated as a valuable timber. See a 
pamphlet by Federico Albert, Chief of the Division of Forests and Water Supply, " La 
Caoba do las Vegas o Eucalyptus robusta " (Santiago, Chile, 1907). 
I Alidiit io!l. The Swamp Mahogany yields but a very small quantity of 
a reddish-brown gum or so-called kino, which contains true gum in its composition, 
and which, therefore, belongs to my one-time " Gummy Group," a group numerically 
much inferior to either the Ruby or Turbid group. 
. It is a medium-sized tree, which may attain a height of 80 feet and more, 
with a st3m diimeter of 3 of 4 feet. 
H;il)ilnl. It is a coast-district species, confined to New South Wales and 
Queensland, and extending from Twofold Bay in the south of New South Wales to 
South Queensland in the north. It does not extend far inland; in the county of 
Cumberland or Sydney district it has not been noted further than Richmond and the 
Lower Hawkesbury. 
For details as to localities see my " Critical Revision of the Genus Eucalyptus," 
Part XXIII, p. 47. 
EXPLANATION OF PLATE 257. 
A. Juvenile loaf, from Bondi, Sydney. 
B. Flowering twig. 
c. Fruits. 
n and c from Manly, Sydney. 
PHOTOGRAPHIC ILLUSTRATIONS. 
1. !:.!.- nl :ll ,!n robusta. Concord Park, Sydney. 
2. Sime tree, showing bark. (R. H. Camb.age, photo.) 
3. Swamp Mahogany (E. rob'^la), Wyong, N.S.W. Girf.h J2 feet barrel 35 feet. (F. A. 
Kirton, photo.) 
