eautiful in effect.

Valves were invented and first introduced in Prussia about A.D. 1815.
At first there were two, but there are now generally three. In this
country and France they are worked by pistons, which, when pressed
down, give access for the air into channels or supplementary tubings
on one side of the main bore, thus lengthening it by a tone for the
first valve, a semitone for the second, and a tone and a semitone for
the third. When released by the finger, the piston returns by the
action of a spring. In large bass and contralto instruments, a fourth
piston is added, which lowers the pitch two tones and a semitone. By
combining the use of three valves, lower notes are obtained--thus, for
a major third, the second is depressed with the third; for a fourth,
the first and third; and for the tritone, the first, second, and
third. But the intonation becomes imperfect when valves are used
together, because the lengths of additional tubing being calculated
for the single depressions, when added to each other, they are too
short for the deeper notes required. By an ingenious invention of
compensating pistons, Mr. Blaikley, of Messrs. Boosey's, has
practically rectified this error without extra moving parts or altered
fingering. In the valve section, each altered note becomes a
fundamental for another harmonic scale. In Germany a rotary valve, a
kind of stop cock, is preferred to the piston. It is said to give
greater freedom of execution, the closeness of the shake being its
best point, but is more expensive and liable to derangement. The
invention of M. Adolphe Sax, of a single ascending piston in place of
a group of descending ones, by which the tube is shortened instead of
lengthened, met, for a time, with influential support. It is suitable
for both conical and cylindrical instruments, and has six valves,
which are always used independently. However, practical difficulties
have interfered with its success. With any valve system, however, a
difficulty with the French horn is its great variation in length by
crooks, inimical to the principle of the valve system, which relies
upon an adjustment by aliquot parts. It will, however, be seen that
the invention of valves has, by transforming and extending wind
instruments, so as to become chromatic, given many advantages to the
composer. Yet it must, at the same time, be conceded, in spite of the
increasing favor shown for valve instruments, that the tone must issue
mo