It shows the difference of effects between one climate and another, that in Brazil the more porous and open-grained timbers are most subject to the attacks of the white ant, especially if they are in contact with the earth; but _in Australia_ it is the reverse, for there it is the hardest description of timber that those insects first attack. There is one wood in particular, in common use, to which this remark applies, namely, “Iron Bark.” Its density is so great that it sinks in water, and its strength is extraordinary, and yet the wood the white ants are particularly fond of. In the West Indies, the ants prefer hard woods.
_At Bahia_, the timber is less affected by the termite than _in Pernambuco_; but even in the latter place the white ant does not like dry places with a free circulation of air.
Mr. Shields, when on a short visit to Pernambuco, examined some timber bridges, and in one, which had only been constructed three years, he found the ends of the timber had been placed in contact with the moist clay; at those places he could readily knock off the crust of the wood, and the interior of the wood was almost filled with white ants: the decay was augmented by the contact of the wood with the moist clay. We have been informed that timber for the Government works is stored to the depth of about 1 foot 6 inches in the sea-sand, to protect it from the white ants and the _teredo_; and that in Pernambuco, since the establishment of the gas-works, the Brazilian engineers and constructors “pay” over the ends of all timbers used in buildings with coal-tar.
_In Ceylon_, no timber--except ebony and ironwood, which are too hard; palmyra, in _northern_ Ceylon; and those which are strongly impregnated with camphor or aromatic oils, which they dislike--presents any obstacle to their ingress. Sir Emerson Tennant, in his work on Ceylon, says: “I have had a cask of wine filled, in the course of two days, with almost solid clay, and only discovered the presence of the white ants by the bursting of the corks. I have had a portmanteau in my tent so peopled with them in the course of a single night that the contents were found worthless in the morning. In an incredibly short time a detachment of these pests will destroy a press full of records, reducing the paper to fragments; and a shelf of books will be tunnelled into a gallery, if it happened to be in their line of march.”