Bagnall. — Kahikatea as a Buildimi Timber. 577 



Akt. LXXII. — Kahikatea as a Building Timber. 



By L. J. Bagnall. 

 [Read before the Auckland Institute, 18th October, 1886.1 



In a jDaper read before this Institute by Mr. E. Bartley, on 

 " The Building Timbers of Auckland," and printed in the last 

 volume of " Transactions," a somewhat one-sided reference is 

 made to kahikatea, and a very low estimate of its value as a 

 building timber is given. As I have had during the past fifteen 

 years excellent opportunities of observing the capabilities of the 

 kahikatea of the Thames Valley, I propose placing before you 

 such facts as will, I believe, give a more just appreciation of its 

 merits. 



The kahikatea of the Thames grows upon low-lying, wet 

 ground, but whether it is better or worse than that which grows 

 upon high and dry land, I am not in a position to say, as I have 

 had no experience of the latter. I may here state that I have 

 not been able to obtain any satisfactory reasons for supposing 

 that there is any material difference in the two kinds, or that 

 that growing on dry ground is any more durable than that which 

 is found in the swamps. There are two marked features notice- 

 able in kahikatea trees, as will be seen from the sections of two 

 trees which I have here. The one is quite white all through, 

 while the other shows very plainly the yellow heart, and the 

 outer white, or sap part. The heart is much harder, and con- 

 tains seams of gum near the centre. In the Thames forests the 

 latter kind is by far the most abundant, the white kind being 

 comparatively rare. The heart in kahikatea is proportionately 

 much less than in kauri, totara, or rimu, and is irregular in 

 form. Logs newly felled are so heavy that many of them barely 

 float, and about 10 per cent, will sink ; but, when cut into 

 boards, and dried, the timber is reduced in weight fully 30 per 

 cent. Sawn kahikatea presents a nice appearance. It is clean, 

 and generally straight-grained, and, when dressed and polished, 

 looks well in ceilings and for other indoor purposes. It takes a 

 greater strain to break it than kauri, and does not shrink end- 

 ways. Apart from the question of its durability, it is otherwise 

 equal to any of our other timbers used for building purposes. 



It is, however, more particularly to its durability that I 

 desire ^ to call attention, knowing that this is one of the first 

 requisites of a building timber. For eighteen years the kahi- 

 katea of the Thames has been used in considerable quantities in 

 building, but before the first sawmill was started several houses 

 were built of kahikatea, sawn by hand. One of these houses is 

 situated at Te Puke, and was built in 1850 by the late Mr. 

 Thorpe, one of the first European residents of Ohinemuri. I 



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