Menippus of Sinope. Having weighed the probable pains and pleasures of approaching old age, he decided that life had nothing left for which he greatly cared, and drowned himself. He is said to have written several works, which he afterwards burnt. Of one, entitled Χρείαι, Diogenes preserves a single line (vi. 6).
METRODORUS, the name of five philosophers.
1. Metrodorus of Athens was a philosopher and painter who flourished in the 2nd century B.C. It chanced that Paullus Aemilius, visiting Athens on his return from his victory over Perseus in 168 B.C., asked for a tutor for his children and a painter to glorify his triumph. The inhabitants suggested Metrodorus as capable of discharging both duties, and it is recorded that Aemilius was entirely satisfied (see Pliny, Nat. Hist. xxv. 135).
2. Metrodorus of Chios was an important member of the Atomistic school. A pupil of Nessus, or, as some accounts prefer, of Democritus himself, he was a complete sceptic. He accepted the Democritean theory of atoms and void and the plurality of worlds, but held a theory of his own that the stars are formed from day to day by the moisture in the air under the heat of the sun. His radical scepticism is seen in the first sentence of his Περὶ φύσεως, quoted by Cicero in the Academics ii. 23 § 73. He says, “We know nothing, no, not even whether we know or not!" and maintains that everything is to each person only what it appears to him to be. Metrodorus is especially interesting as the teacher of Anaxarchus, the friend of Pyrrho, and, therefore, as the connecting link between atomism proper and the later scepticism. It cannot be decided whether a work entitled the Τρωϊκά quoted by Athenaeus (iv. 184 a) is by this, or another, Metrodorus. The same difficulty is found in the case of the Περὶ ἱστορίας referred to by the scholiast on Apollonius.
3. Metrodorus of Lampsacus was the disciple and intimate friend of Epicurus, and is described by Cicero (de Fin. ii. 28. 92) as “almost a second Epicurus.” He died in 277 B.C. at the age of fifty-three, seven years before his master, who adopted his children and in his will commended them to the care of his pupils. The wife of Metrodorus was Leontion, herself, like many other women of the time, a member of the Epicurean society. Athenaeus (vii. 279 F.) quotes from the words of Metrodorus showing that he was in entire agreement with Epicurus, and Was, if possible, even more dogmatic in his doctrine of pleasure. He censures his brother, Timocrates, who, though professedly Epicurean, maintained the existence of pleasures other than those of the body.
4. Another Metrodorus of Lampsacus was a pupil of Anaxagoras, and one of the earliest to attempt to interpret Homer allegorically. He explained not only the gods but also the heroes Agamemnon, Achilles, Hector, as representing primary elements and natural phenomena.
5. Metrodorus of Stratonice was a pupil, first of Apollodorus, and later of Carneades. He flourished about 110 B.C., and is reputed to have been an orator of great power. His defection from the Epicurean school is almost unique. It is explained by Cicero as being due to his theory that the scepticism of Carneades was merely a means of attacking the Stoics on their own ground. Metrodorus held that Carneades was in reality a loyal follower of Plato.
METRONOME (Gr. μέτρον, measure, and νόμος, law), an
instrument for denoting the speed at which a musical composition
is to be performed. Its invention is generally, but falsely,
ascribed to Johann Nepomuk Maelzel, a native of Ratisbon
(1772–1838). It consists of a pendulum swung on a pivot; below
the pivot is a fixed weight, and above it is a sliding weight that
regulates the velocity of the oscillations by the greater or less
distance from the pivot to which it is adjusted. The silent
metronome is impelled by the touch, and ceases to beat when this
impulse dies; it has a scale of numbers marked on the pendulum,
and the upper part of the sliding weight is placed under that
number which is to indicate the quickness of a stated note, as
M.M. (Maelzel’s Metronome) 
＝60, or 
＝72, or 
＝108, or the
like. The number 60 implies a second of time for each single
oscillation of the pendulum—numbers lower than this denoting
slower, and higher numbers quicker beats. The scale at first
extended from 50 to 160, but now ranges from 40 to 208. A more
complicated metronome is impelled by clock-work, makes a
ticking sound at each beat, and continues its action till the works
run down; a still more intricate machine has also a bell which
is struck at the first of any number of beats willed by the
person who regulates it, and so signifies the accent as well as the
time.
The earliest instrument of the kind, a weighted pendulum of variable length, is described in a paper by Etienne Loulié (Paris, 1696; Amsterdam, 1698). Attempts were also made by Enbrayg (1732) and Gabory (1771). Harrison, who gained the prize awarded by the English government for his chronometer, published a description of an instrument for the purpose in 1775. Davaux (1784), Pelletier, Abel Burja (1790) and Weiske (also 1790) described their various experiments for measuring musical time. In 1813 Gottfried Weber, the composer, theorist and essayist, proposed a weighted ribbon graduated by inches or smaller divisions, which might be held or otherwise fixed at any desired length, and would infallibly oscillate at the same speed so long as the impulse lasted. Stöckel and Zmeskall produced each an instrument; and Maelzel made some slight modification of that by the former, about the end of 1812, which he announced as a new invention of his own, and exhibited from city to city on the Continent. It was, as nearly as can be ascertained, in 1812 that Winkel, a mechanician of Amsterdam, devised a plan for reducing the inconvenient length of all existing instruments, on the principle of the double pendulum, rocking on both sides of a centre and balanced by a fixed and a variable weight. He spent three years in completing it, and it is described and commended in the Report of the Netherlands Academy of Sciences (Aug. 14, 1815). Maelzel thereupon went to Amsterdam, saw Winkel and inspected his invention, and, recognizing its great superiority to what he called his own, offered to buy all right and title to it. Winkel refused, and so Maelzel constructed a copy of the instrument, to which he added nothing but the scale of numbers, took this copy to Paris, obtained a patent for it, and in 1816 established there, in his own name, a manufactory for metronomes. When the impostor revisited Amsterdam, the inventor instituted proceedings against him for his piracy, and the Academy of Sciences decided in Winkel’s favour, declaring that the graduated scale was the only point in which the instrument of Maelzel differed from his. Maelzel’s scale was needlessly and arbitrarily complicated, proceeding by twos from 40 to 60, by threes from 60 to 72, by fours from 72 to 120, by sixes from 120 to 144 and by eights from 144 to 208. Dr Crotch constructed a time measurer, and Henry Smart (the violinist, father of the composer of the same name) made another in 1821, both before that received as Maelzel’s was known in England. In 1882 James Mitchell, a Scotsman, made an ingenious amplification of the Maelzel clock-work, reducing to mechanical demonstration what formerly rested wholly on the feeling of the performer.
Although “Maelzel’s metronome” has universal acceptance, the silent metronome and still more Weber’s graduated ribbon are greatly to be preferred, for the clock-work of the other is liable to be out of order, and needs a nicety of regulation which is almost impossible; for instance, when Sir George Smart had to mark the traditional times of the several pieces in the Dettingen Te Deum, he tested them by twelve metronomes, no two of which beat together. The value of the machine is exaggerated, for no living performer could execute a piece in unvaried time throughout, and no student could practise under the tyranny of its beat; and conductors of music, nay, composers themselves, will conduct the same piece slightly slower or quicker on different occasions, according to the circumstances of performance.
METROPOLIS (Gr. μήτηρ, mother, πόλις, city), properly a mother-city, and so the name of the parent state from which colonies were founded in ancient Greece (see Greece, sect. History, Ancient). The word was used in post-classical Latin for
the chief city of a province, the seat of the government, and in particular ecclesiastically for the seat or see of a metropolitan bishop (see Metropolitan). It is thus used now for the capital
of a country, which contains the various official buildings of the administrative departments, the Houses of Parliament, &c. In the case of London, the term “metropolitan” is sometimes applied to the whole area including the “City of London,” e.g. “Metropolitan Asylums Board”; and sometimes, as in “Metropolitan Police,” excludes the City, which has its own police force (see London).
METROPOLITAN (Lat. metropolitanus, Gr. μητροπολίτης in the Christian church, the title of a bishop who has the oversight over bishops of subordinate sees. In the Western church
