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is fixed to the stick transversely, so that when the stick is held 
vertically the strap is horizontal. The instrument is made as 
as follows: — A strip of leather two inches wide and three to four feet 
long is taken, and a drawing-pin or small nail fixed at one end with 
the point projecting through the leather. The strap is then nailed 
across a stout stick three and a half feet long, fixing the strap a 
distance of three feet from the end of the stick, and allowing three 
inches of that end of the strap which carries the drawing-pin to pro- 
ject across the stick. The face of the strap next the stick is covered 
with a strip of white paper, and the apparatus is ready for use. 
To measure a tree stand the stick upright against the tree, 
girdle the trunk with the leather strap, and measure and at the same 
time, record, the girth by pricking a small hole in the paper. In this 
way the strip of paper becomes covered with a number of small 
pricked holes each of which represents the girth of a tree, taken at 
three feet from the ground, and the measure of which is the distance 
of the hole from the pin point when the strap is laid out fiat. 
Each tree as measured is chalk marked and at the end of the day 
the straps are “ counted/' This is done in this way : the strap is 
laid flat on a table and distances in inches ruled off, measuring from 
the pin point. The number of pricked holes in each section gives 
the number of trees of girth corresponding to that section, measured 
in the day . 
The advantages of this method are that it is very rapid, it does 
not demand skilled labour in the field as there is no reading of tapes 
or writing to be done, and above all it gives the daily returns in a 
suitable form for calculating averages, and the number of trees of 
each inch or girth, which is valuable information. The disadvantage 
is that individual trees are not identified. 
In working out the averages two corrections should be applied the 
first is the addition of half-an-inch to allow for the measurements 
being taken in even inches, thus 254 trees of girth 26 to 27 inches 
have the true average of 26-5 inches ; the second correction allows 
for the thickness of the strap and errors in not straining the strap 
sufficiently tight in measuring. This error is corrected by subtract- 
ing half-an-inch from the average results. If therefore trees of say 
26 to 27 inches as measured be called of average 26 inches the two 
errors will practically cut each other out. Except for very important 
work it is not necessary to consider these corrections. 
CREOSOTING RUBBER. 
In a lecture given by Dr. WiLLlS at the close of the Rubber 
Exhibition in Ceylon he raises the question of creosoting rubber. 
He says “ on the whole smoked rubber with creosote turned out 
better in quality than rubber unsmoked. He did not say plain 
smoking would have much to do with it but there was little doubt 
that creosote did strengthen the rubber. That raised the question 
whether they ought to make use of creosote. He thought that it 
yh-i% 
