MtTSlC. 533 



by Palestiina, in 1555, and Monte verde, in 1582. In the fifteenth 

 century, notes were first varied in shape, to distinguish their length 

 or time ; but bars were not employed to divide the piece into equal 

 measures, till the beginning of the seventeenth century. The first 

 opera, called Dap/me, the words by Rinuccini, and the music by 

 Jacopo Peri, was composed and performed at Florence, in the year 

 1598. It was followed, in 1600, by the first oratorio, entitled Dell' 

 Auima e del Corpo, composed by Emilio del Cavaliere, partly in 

 imitation of the ancient recitative. The opera differs from the sim- 

 ple drama, in uniting the charms of music to those of poetry ; and 

 hence it has been called by the Italians musica parlante, or speaking 

 music. The oratorio, consisting of a sacred poem set to music, is, 

 we think, the noblest and grandest of musical productions. As a 

 sequel to the history of Music, a few of the best operas and oratorios 

 will be mentioned in the concluding section of this chapter. 



The study of Music, may, we think, be comprised under the heads 

 of Physical Theory of Music ; Musical Notation ; Musical Compo- 

 sition and Execution ; and Musical Productions. 



1. The Physical Theory of Music, depends upon laws of 

 Acoustics, the statement of which has been reserved for the present 

 place. Music is either a succession, or a combination of sounds : 

 the former producing melody, and the latter harmony. Musical 

 sounds, or tones, are caused by regular vibrations of the particles of 

 the air; which vibrations are transmitted from sounding bodies to 

 the ear. The grave, or low tones, are caused by slower vibrations 

 of the air, and are sounded by the longest pipes, or strings, corres- 

 ponding to the left hand keys of the organ, or piano. The more 

 acute, or higher sounds, result from more rapid vibrations, from 

 shorter strings or pipes. The tone of a musical string, depends 

 upon its tension, its diameter, and its length. Hence, if its tension, or 

 tightness, and its diameter continue the same, we may vary its length 

 to produce various tones ; and express these tones by means of the 

 lengths to which they correspond : for the number of vibrations in a 

 given time is inversely proportional to these lengths. 



Thus, two similar strings, of the same length, will vibrate in equal 

 times, or unison; both sounding the same note. But if one of the 

 strings be only half as long as the other, it will vibrate twice as 

 rapidly ; and produce a sound called an octave above that of the 

 longer string; because this interval is made to comprehend eight 

 notes, including the two in question, in the diatonic scale. If the 

 strings, and consequently their vibrations, be in the ratio of 2 to 3, 

 the resulting interval is called a perfect fifth : but the ratio of 3 to 4 

 gives a minor fourth ; the two extreme notes, in all these cases, 

 being counted. The ratio of 4 to 5, corresponds to the interval of a 

 major third ; and the ratio of 3 to 5, or a major third above the 

 minor fourth, gives the interval of the major sixth. The ratio of 8 

 to 9, gives the major second ; and that of 8 to 15, or a major third 

 above the perfect fifth, gives the major seventh ; which completes 

 the eight notes of the octave, in the diatonic, or natural scale. In 

 passing from one of these notes to the next, the ratio will be found 

 to vary ; showing that they are at unequal intervals, which are com- 



2Y2 



