Fig. 2.—PLAN VIEW OF THE XYLOPHONE.
As the name, "instrument of wood and straw," indicates, the xylophone (which Fig. 1 shows the mode of using) consists of small pieces of wood of varying length, and narrow or wide according to the tone that it is desired to get from them. These pieces of wood are connected with each other by cords so as to form a triangular figure (Fig. 2) that may be managed without fear of displacing the parts. The whole is laid upon bands of straw designed to bring out the sounds and render them stronger and purer. The sounds are produced by striking the pieces of wood with a couple of small hammers. They are short and jerky, and, as they cannot be prolonged, nothing but pieces possessing a quick rhythm can be executed upon the instrument. Dances, marches, variations, etc., are played upon it by preference, and with the best effect.
The popularity of this instrument is making rapid progress, and it is beginning to be played in orchestras in France [as it has been in America for many years]. A method of using it has just been published, as well as pieces of music adapted to it, with piano, violin, orchestra, etc., accompaniment.
ELECTROTYPING.
This eminently useful application of the art of electrotyping originated with Volta, Cruickshank, and Wollaston about 1800 or 1801. In 1838, Spencer, of London, made casts of coins, and cast in intaglio from the matrices thus formed; in the same year Jacobi, of Dorpat, in Russia, made casts by electro deposit, which caused him to be put in charge of the work of gilding the dome of St. Isaac at St. Petersburg.
Electrotyping for the purposes of printing originated with Mr. Joseph A. Adams, a wood-engraver of New York, who made casts (1839-41) from wood-cuts, some engravings being printed from electrotype plates in the latter year. Many improvements in detail have been added since, in the processes as well as the appliances. Robert Murray introduced graphite as a coating for the form moulds. He first communicated his discovery to the Royal Institution of London, and afterward received a silver medal from the Society of Arts.
BLACKLEADING THE FORM.
The process of electrotyping is as follows: The form is locked up very tightly, and is then coated with a surface of graphite, commonly known as blacklead, but it is a misnomer. This is put on with a brush, and may be done very evenly and speedily by a machine in which the brush is reciprocated over the type by hand-wheel, crank, and pitman. A soft brush and very finely powdered graphite are used; the superfluous powder being removed, and the face of the type cleaned by the palm of the hand.