Edward Bartley
Edward Bartley, like many of his generation, was passionate
about the natural sciences and the new understandings of the natural world
which occurred with increasing rapidity during the 1800’s.
We think of our own
time as being one of the greatest technological breakthroughs, but the reign of
Queen Victoria saw phenomenal advances across a range of fields.
The Museum Institute was a valuable forum for information
exchange on scientific and historical matters.
As an early member, Edward
attended the meetings and lectures regularly and, on occasion, presented
material himself on topics which interested him personally or professionally.
On arriving in 1854 as a young man, Edward worked in the
building trade, with his brother Robert. The construction of the Supreme Court
building was an unusual subcontract for them, as it enabled the brothers to
work in stone, as they had been used to do in the Channel Islands.
Predominantly construction in the Auckland province was in timber – a plentiful
resource in the new colony. Yet surprisingly little was known of the native
timbers. Their properties and usefulness were still disputed, even after Anton
Seiffert had produced outstanding cabinetmaking with carved and marquetry
detail using local species.
Edward observed and experimented with local woods and, as an
architect, was particularly fond of exploiting their decorative value for
interior work. In 1885 he presented a paper to the Institute on the subject of
native timbers and their suitability for use in building. An extract of text
from this presentation is reproduced for you here:
By Edward Bartley, Architect.
[Read before the Auckland Institute, 30th November, 1885.]
Specimens
of Timber to Illustrate the Paper.
Kauri.—Four specimens: Red, white, black, and a soft kind
from Tairua.
Piece of kauri joist destroyed by dry rot.
Piece of kauri destroyed by grubs.
Piece of window-sill from St. Andrew's Church, built in
1847.
Rimu.—Piece of 12 in. x ¾ in. board, to show the difficulty
in discriminating between sap and heart.
Totara.—Piece with the commencement of small spots of decay.
Kahikatea.—Piece of flooring completely destroyed by the
grub.
There are only four kinds of New
Zealand timbers used in Auckland for building purposes. I place them
in the following order of merit: Kauri, rimu, totara, and last kahikatea. After
touching on these various timbers, I propose to say a few words on seasoning
and decay of timber. Permit me to remark that the statements are not gathered
from hearsay, but from thirty years' experience in the building trade in Auckland. I have of late
years taken down buildings that I either took part in erecting or saw erected;
I have had, therefore, many opportunities of studying the durability and other
characteristics of our Auckland-grown timbers.
First, the kauri (Dammara
australis).—I have here specimens of four kinds of kauri: the red, white,
black, and a soft kind, quite distinct in grain and quality from the others,
which I will hereafter explain. The red kauri is the best general building
timber; it is well adapted for heavy framework, beams, joists, and the like; it
is close-grained, rather gummy, very durable, but is liable to cast and twist;
it shrinks endways as well as in width. The shrinking endways is a great
drawback to kauri, and more especially this kind. I have known a forty feet
beam shrink 1 ½ inches in length. I have also known a weatherboard shrink ¾ of
an inch in twenty feet, and most of us will remember ceiling mouldings and
other joiners' work shrinking so as to quite disfigure the building. This red
kauri should only be used for beams or other framework, and not for mouldings
or joiners' work. The next is the white kauri, a tough kind of timber; will
bear a greater breaking strain than the red, but not so durable; I have seen it
quite soft in a few years; it is a splendid timber for moulding and joiners'
work. The shrinking endways is almost nil,
if worked up after a fair amount of seasoning, neither will it cast. It is
largely used by boat-builders on account of its readiness to bend. Black kauri
is not very abundant, it comes from the west coast of the island, it is only
fit for rough work, is heavy with gum, and the most durable of all; in fact,
for fencing-posts or the like, I believe it would last as long as puriri. I need
hardly say it is not fit for mouldings or joiners' work; it is so hard it would
require very strong machinery to work it, and after being worked it would cast
into all shapes. The last specimen of kauri (No. 4) is the timber for joiners' work and mouldings; there is a peculiar
grain marking in this kind of kauri not to be found in any of the other
specimens—this kind should only be used for mouldings and joiners' work. We
have often heard it remarked that kauri is noted for its casting, twisting, and
shrinking: well, this last kind of kauri will neither cast, twist, nor shrink
endways. I have seen slight scantlings, say 3 in. by 3 in., 20 feet long, quite
straight, after being exposed to the weather without any care. I have seen
joiners' work made up out of this timber standing as well as cedar. I have
already said it should only be used for joiners' work and mouldings, it is so
light and soft; it should never be used for beams or heavy framework; but if
this kind of kauri and the white only were used for joiners' work and
mouldings, we should seldom hear of ruined ceilings, and twisted doors and
sashes. This kind of kauri is only found in the Tairua District.
The next timber on my list is the rimu (Dacrydium cupressinum). It is known in the South
Island as red pine. The rimu, I believe, grows in the South to a
very large tree, but in this province the average size tree is two feet six
inches to three feet diameter; it is a timber with a large proportion of
sap-wood—a two-feet diameter log will have nine inches of sap-wood, leaving
only six inches of heart, the heart not being very well defined. By this
specimen of rimu (a board twelve inches wide) the difficulty in discriminating
between sap and heart will be seen, even by an expert. There is a hard white gum,
and frequently many shakes, near the heart, that renders this tree unfit for
boards, but it answers well for scantlings, joists, and framework. The
sap-wood, if exposed to weather or damp, will not last, but the heart is very
durable. I have known rimu fences standing many years. Of course, with kauri so
plentiful, we have not used much rimu; but at the rate the kauri is being cut,
before many years we shall, I am sure, have to fall back on the rimu. Picked
heart of rimu is a very good furniture wood, and very suitable for church
furniture.
Totara (Podocarpus
totara) is the third timber of importance. It is largely used in the South
for building purposes, but in Auckland
we only know it as a good “pile” timber, and for that purpose it has not been
equalled by either native or imported timbers. I have seen a “stringer” taken
from Queen-street
Wharf quite sound, after
being under water twenty-eight years. Of course it was heart, the sap will not
last; hence the folly of using round sticks for piles. All piles should be
squared timber—all heart. It is at times specified for plates and window sills,
with a view, I presume, that it will last longer than kauri. I think this is a
mistake: my experience is that it will not last as long as the heart of red
kauri. There is a small “rot” speck found in the heart of mature trees; I have
here a specimen cut from a new plank with this kind of decay, still the totara
must be classed as one of our most durable timbers.
The last, and the worst of our building timbers, is the
kahi-katea (Podocarpus dacrydioides).
It will decay very soon, exposed to the weather or damp—in damp situations it
will not certainly last longer than four years—and inside, or under cover, such
as flooring, ceiling or lining, it is attacked by a small grub, completely
destroying the inside of the scantling or board. I have here a specimen of
kahikatea flooring destroyed by this grub; the destruction is so complete that
I have known a floor rendered dangerous to walk on, the chairs having gone
through in many places. I consider kahikatea is far inferior to all sap kauri.
If used for rough lining, the perforations made by this grub will appear
through scrim and paper of the room; in an instance that came under my notice,
one kahikatea board had been fixed for rough lining, the remainder being sappy
kauri: the board, scrim, and paper were quite destroyed, like a band nine
inches wide, the remaining lining being quite sound. It is said that kahikatea
grown on high ground grows better than that grown on low ground; but the
greater portion, I should say nine-tenths, grows on flat swampy districts.
Seasoning
and Decay of Timber.
The causes of decay are various, the worst being “dry rot”—a
term giving a wrong idea of the nature or cause of the decay. I have here a
specimen of heart kauri destroyed by “dry rot.” It is covered with a fungus of
extraordinary growth in Auckland.
I have seen a plant measuring over five feet in diameter. Whether the fungus
grows in consequence of the decay, or the decay is caused by the fungus, I am
not quite clear; but I should rather think the fungus grows after the decay,
and is not the cause of the decay. At any rate we know the first cause is by
using unseasoned timber in unventilated positions, such as a ground-floor
without a space left for ventilation. Nearly if not all the ground-floors on
the east side of Lower Queen-street are decaying with “dry rot.” I have known
12 in. x 3 in. all heart kauri joists quite rotten in twelve years; the joists
will break off in pieces from six inches to two or three feet long, and will be
found flat on the ground, with square ends, the timber always breaking at right
angles to the fibre of the wood. The kauri is also destroyed by a small grub,
similar in some respects to the grub in the kahikatea, but with this
difference: the grub in the kahikatea always bores with the fibre of the wood;
the grub in the kauri will bore in any direction. I have here a sample of kauri
bored with this grub. The sap-wood will be attacked first; but if found in a
building, it will soon go right through, heart and sap falling a prey to it.
One great reason for kauri and other timber decaying is the
constant use of young and unmatured timber. A mature kauri will be at least
five feet diameter, showing well defined sap-wood of not more than three to
four inches. Now, a large quantity of logs cut up in Auckland will not measure more than 2 feet 6
inches to 3 feet in diameter: this size log will have nine inches of sap-wood,
leaving on a log 2 feet 6 inches only 12 inches of heart, and that soft and
white. Next to using young timber is the constant use of unseasoned timber, and
the practice of our mill-owners cutting down trees all the year round, and full
of sap. I consider the trees should be “barked” at least six months before
being fallen; the barking, of course, simply means cutting out a ring of bark,
say four or six inches in width, close to the ground. Another plan, adopted in
America, is to bore two holes right through the trunk, crossing each other in
the middle of the tree; either or both are inexpensive operations, and should
be tried by the mill-owners. As to the time of year for felling our New Zealand
timbers, I consider, if barked or bored as I suggest, it would not matter a
great deal. It will be seen at once that if we get rid of the sap or gum before
falling we have overcome half the difficulty (if not more) experienced in
seasoning. Hence the failure of artificial seasoning by the hot chamber, used a
short time ago by some of the mills, the hot chamber simply baking the outside,
leaving the sap and gum inside the plank. It is a fact known to all carpenters
that kauri will season better in the rain and wind of winter than the hot sun
of summer. Most of us know the effect of new kauri shingles on a tank of water:
the gum and sap is washed out to such an extent by the rain, that the first
water off the roof is like weak turpentine, and dark in colour. Then we have
another cause of decay, consequent upon using unseasoned timber, that is the
injudicious use of tar. It is right to tar a well-seasoned piece of timber, but
utter folly to tar green timber, and all round, as we see repeatedly done in
our buildings and wharves. I have known a 4in. x 3in. plate of heart of kauri
quite rotten in two years, solely on account of being tarred all round; the
proof being that other plates in similar situations, and quite near, were quite
sound. If the durability of timber is to be studied, it should be a rule not to
paint or tar timber before being seasoned. That kauri will last, I have had
many instances brought under my notice. Here is a portion of a window-sill
taken from St. Andrew's Church, built in 1847; it will be found not the least
impaired by thirty-six years' exposure to the weather. It was removed about two
years ago. It was resting on a stone sill; the under side, it will be observed,
has not been painted. Only one other instance: The two first grave fences in
the Auckland Cemetery, erected thirty-three years
ago, are still standing, and quite sound. The posts are of red kauri, and had
been charred.
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