320 
what may be expected. At any rate, the results obtained in our 
experiments indicate clearly that the Ceara rubber tree in Hawaii 
will not only grow and thrive, but will yield profitable returns. 
Further experiments will be carried on in the microscopic exam- 
ination of sections of the Ceara rubber tree to get a basis for 
determining the best method of tapping. Several other species of 
rubber trees will also be tapped and an elaborate series of ferti- 
lizer experiments with rubber is planned. We hope to be able to 
devise a method of fertilizing rubber trees so as to secure an in- 
creased flow of latex during the tapping periods. 
A NEW USE FOR RUBBER. 
An ingenious device has been patented by a Japanese, Koza- 
buro Makimora, for the automatic signalling of shallow water. 
It consists briefly of an airtight rubber disc covering one end of 
an empty cylinder. This cylinder is weighted and towed by 
the ship at the end of a small armored electric cable. The rub- 
ber is bulged in by the pressure of the water, but this is partly 
compensated for by the provision of a spiral spring inside the 
cylinder. When the ship approaches shallow water the apparatus 
drags along the sea bottom,, and as the water pressure lessens, 
the balance between the force of the spiral spring pushing out- 
wards and the force of the water pushing the rubber disc in- 
wards becomes disturbed, and acting upon a simple mechanism, 
rings an electric bell upon the ship. The rubber disc is well 
protected by a perforated cap. 
We are not sufficiently informed to say for certain whether 
the device is entirely practicable for merchant vessels steaming 
at considerable speed, but at any rate there should be a consider- 
able scope for the invention upon survey vessels, ships in un- 
known waters, etc. — India Rubber Journal, April 20. 
LUMBER IMPORTATIONS. 
The lumber importations of the world amount to $285,600,000, 
of which in spite of the fact that its supply is diminishing, the 
United States furnishes 20 per cent. 
Only four per cent, of Great Britain is forested, while Ger- 
many possesses still 26 per cent, of forest land. The countries 
importing most wood are, generally speaking, those on the high- 
est economic plane, which were formerly densely wooded, but 
whose forests have been destroyed. 
