598 QUEENSLAND AGRICULTURAL JOURNAL. [1 Dec., 1899. 
If the wood is perfectly dry, painting the surface, or covering it with a layer 
of some impervious material, may preserve the timber; but if it be at all damp, 
then such a coating will do more harm than good, for it will prevent the escape 
of moisture, even if the surface be exposed to the air. It very often happens, 
therefore, that a carefully painted piece of timber will be destroyed, except for 
a thin external shell. 
The fungus is killed by creosote, mercuric-chloride, copper sulphate, and 
many other mineral poisons; but the mere application of these to the surface 
of the wood is of little avail, as decay may still go on in the interior. Similarly, 
charring is only a very partial protection; the layer of charred wood gives some 
protection, and in charring the wood below will be more or less thoroughly dried, 
but moisture will soon be absorbed again, and then decay may set in. 
The only satisfactory method of preventing the “rot” is to thoroughly 
saturate the timber with the antiseptic solution—that is, the air in the cells and 
vessels must be completely, or at any rate to a large extent, displaced by the 
antiseptic solution, so that the material on which the fungus has to feed is 
effectively poisoned. 
In Bethell’s process, which is perhaps the most generally used, the wood 
is dried, placed in an iron cylinder, and creosote is pumped in at a temperature 
of about 120 degrees Fahr., and at a pressure of about 170 lb. per square inch. 
Very frequently the vessel is first exhausted of air, so as to facilitate the escape 
of the air from the wood. Soft wood may absorb about 10 lb. of creosote per cubie 
foot, whilst hard wood, such as oak, will take very much less. Creosoting seems 
to be the most efficacious method of preserving timber. 
Kyan’s process (Kyanising) consists in saturating the wood with a solution 
of mercuric-chloride (corrosive sublimate) ; in Boucherie’s process, copper 
sulphate is used ; and in Burnett’s, zinc chloride. 
Attacks of Animals——Under some conditions, wood is liable to be attacked 
by animals of various kinds, boring animals occurring both in earth and in 
water. For wood which has to be buried in earth, charring seems to. be a fairly 
good protection, and creosoting also answers very well.—Practical Engineer. 
[Charring posts set in the ground is a very poor protection against the 
attacks of white ants, especially when unsapped posts are used. ‘The charred 
portion cracks, and thus gives clear access to the untouched timber beneath the 
burnt portion.—Hd. Q.A.J.] 
General Notes. 
HOW TO MAKE A SAFETY LIGHT. 
Take a clear glass bottle, such as a small vial, and put a small piece of phos- 
phorus about the size of a pea into it, and see that the cork is sound and a 
good fit. Then get a little of the clearest olive oil, such as that sold for table 
use, heat it to boiling point, and then pour it on top of the phosphorus. Fill 
the bottle about one-third full, and then cork tightly. 
: When requiring a light, remove the cork to allow air to enter, and then 
cork up again, and the whole of the empty space in the bottle will now become 
luminous, giving sufficient light to read the time by a watch, or for other 
purposes when a night light is required. ; 
As the light becomes dim it is only necessary to withdraw the cork again to 
allow a fresh supply of air to enter. ' 
A bottle used like this will continue to give light for some months; but it 
should be kept warm during the winter time, for should the oil become solid 
through the cold the vial will have to be held in the hand for some time to warm 
it sufficiently to act. 
