Numerous expedients have been suggested for getting rid of this destructive insect, some of which have been successful, but the majority only partially so.
In India, the timbers of a house infested with white ants are periodically beaten to drive them away. Of course, this only succeeds for a short time, as they soon return.
The salt vessels plying on the coast of India use oil of tar, and a considerable quantity of castor-oil, mixed with cow-dung mortar, which, while it adheres to the wood, is an effectual protection against ants and rot. The earth oil, or Arracan oil, is considered as good as creosote to protect wood from ants. It can be obtained at Moulmein and Rangoon, in leathern bottles or skins, at about 6_d._ per gallon.
It used to be a practice _in the West Indies_ to destroy whole colonies of ants which had built their nests either on trees or under the roofs of houses, by shooting powdered arsenic out of a quill into an orifice made into their covered ways, along which they ascended and descended from and to the ground.
It has been estimated that the depredations of the white ant in India costs the Indian Government 100,000_l._ a year, which is expended in repairing the woodwork of houses, barracks, bridges, &c.
When Dr. Boucherie gave up his sulphate of copper process for the use of the French public, he received _a national reward_. If the Indian Government is disposed to give us _a national reward_, we could show how it may save at least half the 100,000_l._ a year--which is expended in repairing the damages done by the white ants--with little trouble.
In the Madras Presidency periodical inspections have to be made, not only with regard to the white ant, but with respect to the presence and subsequent germination of vegetable matter or seeds in the mortar. In some instances, where proper precautions had not been taken, roots had formed very rapidly, and of such great size as to bodily dislodge by their pressure large stones from buildings. Therefore, to prevent this germination, a proportion of “Jagherry,” or coarse native sugar, varying from 2 per cent. in ordinary work, to from 5 per cent. to 8 per cent. in arch work, is mixed with the lime.
In 1856, in consequence of the ravages of the white ants in the King’s Magazine, Fort William, India, the flooring and powder racks had to be reinstated. Captain A. Fraser, R.E., had the basement covered with concrete, 4 lb. of yellow arsenic being added to every 100 cubic feet of concrete. In the mortar used for the pillars arsenic was used in the proportion of ½ lb. to every 100 cubic feet of brickwork; a small quantity of arsenic was also mixed with the paint, and ½ lb. (four chittacks) of arsenic was also mixed with every 100 superficial feet of plaster. In 1859 the town mayor reported to the Government that no traces of white ants had since been found either inside or outside the building.