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Mr. MaideD and your readers that the same twist exists in the timber here, the twist being in the same 
direction that Dr. Bell shows is to be found in the timber in Canada. It is quite common to find this 
twist so bad on one side of the tree as to render it almost useless for splitting on that side, whilst on other 
the opposite obtains. As to the cause of this twist it seems to me that it cannot be due to any effect the 
prevailing winds could have on the timber during growth, as the prevailing winds in this portion of 
Australia are from the west. I might say this question is not by any means new to bushmen in this part. 
However, I cannot say that I have heard anyone outside my own immediate circle express an opinion as 
to the cause of this peculiarity in the growth of timber. The opinion I hold myself is that it is due to the 
sun’s influence. Tt is said that certain flowers follow the sun in its course, and I am of opinion the same 
applies to our timber. One thing is certain, we do not see any twist in a tree on the south side, which 
seems to me to be fairly good ground to assume that the sun is the predisposing cause of this peculiarity 
in growth. 
3. Left, to right .— The Wind. 
“Native,” Mulgoa, Hawkesbury River, in Sydney Morning Hrrald, 10th 
April, 1908:— 
His experience is “ that the twist in about 90 per cent, of the forest trees is to the right, and not to 
the left,,'' as mentioned in the Chief Geologist’s (of Canada) letter to Mr. Maiden. An old bush man will fell 
a tree for splitting rails, &c., with a “left-hand twist,” but will pass on a tree with a “ right-hand twist,” 
as showing more twist in the split timber. The prevailing winds have a lot to do with the twist in the 
growth of the young tree sapling, but one would need to take into consideration the heaviest side of the 
top or branches of the sapling, and which will give the greatest impetus or strain on the, young timbers. 
The twist is seldom noticed in hardwood, such as Ironbark or Box, Stringybark, Turpentine, Gum, and in 
most cases Messmate. 
4. Equal number each way .— The Wind. 
J. M'Colgan (Forest Lodge), in the Star, Sydney, 9th April, 190S :— 
Very much of our timber here is affected that way (twist in grain)—so much so that a large per¬ 
centage is rendered useless for splitting purposes, because when a log is split the crack follows the twisted 
grain, with the result that you get your posts or rails with a curl in them like a piece of board that has 
been warped with the sun. It does not matter so much when cutting heavy timber, such as railway 
sleepers, for in case of a tough or twisted tree, the usual practice is to cut grooves lengthwise in the log 
with a broad axe to a, depth of 4 or 5 inches, so that the split has to run straight. But some tre^s have 
such a twist as to be altogether useless. I have seen some that the twist made a complete circuit of the 
barrel of the tree in a length of 10 feet. As to the cause, I am quite satisfied, from close observation, that 
the wind is accountable for it. If you take the trees growing on the hills in the Picton district that are 
exposed to the heavy westerly winds you will find that fully half of them are more or less twisted ; while in 
the gullies, where they are sheltered, this feature is entirely absent. 
Now, as to the statement that 90 per cent, of the twisted trees turn to the left, I think there must 
be some mistake here, for in all my experience I have found that about an equal number turn each wag, 
and now I will explain the cause. Say the heavy winds come from the west, and a tree has an even 
quantity of branches on both sides. Well, that tree would not be affected at all; but if it has more limbs 
on the northern or left-hand side the great and continued pressure of the wind gradually turns it partly 
round, which would cause a twist to the left, while if it had more limbs and branches on the southern side 
the twist would be to the right. • Mr. Maiden asks if this twist is peculiar to any particular kind of tree. 
No, it is not; any tree in an exposed position, and not having an evenly-balanced head, is liable to be 
warped by the heavy winds. 
5. Right and left twist. — Sun, wind. 
Dr. Cleland contributed a “ Note on Twists in the Bark of the Jarrah ( Eucalyptus marginata , 
Sm.).” Of one hundred trees observed in the neighbourhood of Perth, W.A., four showed a decided left 
twist, sixteen a slight left twist, forty-four were straight, twenty-four showed a slight right twist, nine a marked 
l’ight twist, and in three the twist was undecided (i.e., irregular). As there appeared to be no indication 
of a tendency to tree-growth in a spiral direction, the explanation was offered that, when young, a 
