✨ Report on New Zealand woods
38
test them, to be suitable for resisting
cross strains, it is possible that some of
the others may possess the property of
resisting compression as well as tension
in the direction of their fibres. They
may, for instance, prove serviceable as
piles, struts, or tie beams; they may be
able to resist the action of moisture and
even of sea water. To ascertain the
latter point, I have caused to be placed
in a perforated case specimens of the
woods numbered 3, 4, 5, 6, 7, 8, 9, 12,
13, 15, and have had them sunk in the
harbour near Fort Macquarie.
The value of S, that is the constant
representing the strain any particular
wood can bear without fracture, is calculated for each specimen. As a means
for comparison it may be stated that the
value of S in the following known woods
has been stated by Barlow to be as follows:
Superior English Oak, S = 2037 to 2262
Ash ............................... 2037
Elm ............................... 1031 to 1206
Birch ............................. 1826 to 2037
I have not considered it necessary to
calculate in any case the value of E, that
is the constant representing the elasticity
of the wood; but the results given in the
accompanying table are sufficient for this
purpose, should the elasticity of any particular specimen be required.
To decide with confidence on the value
of those New Zealand woods which have
exhibited desirable properties, further
trials would be necessary. At present
I would suggest that other specimens of
Nos. 3, 6, 7, 8, 9, 12, of the table, say four
of each kind, in length not under 5 feet 6
inches and 3 inches by 2 in. scantling, be
obtained and be submitted to further test.
E. W. WARD,
CAPT. R. ENGINEERS.
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Wellington Provincial Gazette 1857, No 4
✨ LLM interpretation of page content
🌾
Report of trials on New Zealand woods
(continued from previous page)
🌾 Primary Industries & Resources20 December 1856
Woods, Experiments, Strength, Kauri, Totara, Rata, Rimu, Hinau, Miro, Manuka, Mangaia, Rewa Rewa, Kohe Kohe, Mapau, Tawa, Tawiri, Kahika, Towhai, Matai
- E. W. Ward, Capt. R. Engineers