proper choice of woods for the book-case: these are cedar, cypress, mahogany, sandal, or very dry and sound oak. All these are compact or of very strong aroma, and are such as insects do not like to pierce. Another source of danger is the use of chemicals in the binding of books.
The insects that make ravages in books multiply very rapidly, and very few libraries are free from them. The microscopic eggs that are left by the female give birth to a small grub, which pierces the leather boards and book for its nourishment, and to get to the air. These are familiarly called bookworms, but by the scientific world they are known as hypothenermus eruditus which eats the leather, and anobium striatum which bores through the paper. The larvæ of the dermestes also attack wood as well as books.
An instance of how these insects were once managed:—
M. Fabbroni, Director of the Museum of Florence, who possessed a magnificent library, found, after a year's absence, in the wood and furniture, great havoc made by insects, and his books spoilt by the larvæ, so much so that it gave a fair promise of the total destruction of the whole, unless he could find a method to exterminate the pests. He first painted the holes over with wax, but shortly after he found new worms which killed every particle of wood they touched. He plunged the ordinary wood in arsenic and oil, and other portions he anointed once every month with olive oil, in which he had boiled arsenic, until the colour and odour announced that the solution was perfect. The number then diminished. But a similar method could not be employed for books. M. Fabbroni resolved to anoint the back and sides with aquafortis; in an instant the dermestes abandoned their habitation, and wandered to the wood; the oil having evaporized they commenced to develop again, and again began their attacks on the newly bound books. He saw amongst the many spoilt books one
