XXVI.] IRON-BARK. 199 
TaBLe C. 
Vertical or Crushing Strain on cubes of 6 inches. 
| No. 13. | No. 14. | Total. | Average. | Dittoon 
I square 
Tons. Tons. | Tons. Tons. inch. 
175 | 195 | 370 | x85: | 514 
E = 930950. S = 2264. 
THE IRON-BARK TREE (Eucalyptus resinifera) 
is found very widely spread over a large part of Aus- 
tralia, and is considered to be abundant. It is a lofty 
and erect tree of moderate circumference, and yields 
timber of from 20 to 40 feet in length, by from 11 to 16 
or 18 inches square. It is believed to have been named 
as above by some of the earliest Australian settlers, on 
account of the extreme hardness of its bark; but it 
might with equal reason have been called iron-wood. 
The wood is of a deep red colour, very hard, heavy, 
strong, extremely rigid, and rather difficult to work. 
It has a plain straight grain, and the pores, which are 
very minute, are filled with a hard, white, brittle secre- 
tion. The tree is generally sound, but liable to the 
defect of both heart and star-shake, and on this account 
it is not usually very solid about the centre, consequently 
the timber cannot be employed with advantage except 
in stout planks or large scantlings. 
It is used extensively in ship-building and engineer- 
ing works in Australia, and in this country it is employed 
in the mercantile navy for beams, keelsons, and in many 
ways in the construction of ships, especially below the 
line of flotation, where a heavy material is not con- 
sidered objectionable. For civil architecture, the orna- 
mental and the domestic arts, it is not, however, likely 
to be in much request, its extreme hardness and great 
weight precluding it from general use. 
