air, which passes through into the large open space between the ceiling and roof, and from thence into a ventilating shaft.
The best artificial lighting of a library is undoubtedly that by electricity; first employed, as is believed, at the Liverpool Free Public Library, and shortly afterwards at the British Museum. Not only does it keep the air pure, and at an even temperature, but it has no products of combustion, like those from gas, to rot the bindings of the books and dirty the decorations of the rooms. The expenses of installation and maintenance have debarred many libraries from adopting it, but in places where gas is high in price, it seems that there is but little difference in the cost. The experience of the Chelsea Public Library may be useful. The gas bill at the central library in 1891, 1892, and 1893 averaged £123, 2s. 10d. per year at 2s. 10d. per 1000 cubic feet. The electric light was then introduced, supplied by a company who charge 5d. a Board of Trade unit. The cost for 1894 was £134, 14s. 2d.; for 1895, £132, 8s. 9d.; and for 1896, £149, 4s. 2d. In addition to this charge, an outlay of about £3 yearly has been paid for new lamps. The initial cost of the installation was £325, and for this 218 lamps were fitted, about half being 16 candle-power, and the rest 8 candle-power.
The Newcastle-upon-Tyne Public Library is also lit by electricity. In this case gas is much cheaper than at Chelsea, the price being only 1s. 10d. per 1000 cubic feet. The initial expense of installation
