The compositions of this master, which have been of marked importance in connection with the progress of stringed instruments, are characterized by a noble sweetness, a genuine pathos, deep science and great nicety of art. It belongs to him, as a distinction, to have first fixed (about 1768) the character of three several classes of instrumental composition—the _trio_, the _quartett_, and the _quintett_. In the trio, he was followed by Fiorillo, Cramer, Giardini, Pugnani, and Viotti; and in the quartett, by Giardini, Cambini, Pugnani, and, in another style, by Pleyel, Haydn, Mozart, and Beethoven; while, in his quintetts for _two_ violoncellos, he may be said to have no successor but Onslow. His productions of this last species, of which he has left no fewer than ninety-three—for he was little inferior to Haydn in fecundity of genius—are particularly deserving of study; and it was the remark of Dr. Burney, that he had supplied the performers on bowed instruments, and the lovers of music in general, with more excellent compositions than any other master belonging to that time, except Haydn. His manner, as the same writer adds, “is at once bold, masterly and elegant; and there are movements in his works of every style, and in the true genius of the instruments for which he wrote, that place him high in rank among the greatest masters who have ever written for the violin or violoncello.” “As in the symphonies of Haydn,” says a writer in the _Harmonicon_, “so in the quintetts of Boccherini, we observe the genuine stamp of genius, differing in the manner, but alike in the essence. Boccherini had studied, profoundly and thoroughly, the nature and capabilities of the _violoncello_. He composed nearly the whole of his music for this instrument, and was the first who wrote quintetts for two violoncellos. Striving to impart to these productions the sweet, pathetic, and, if the expression may be allowed, the religious character which distinguished most of his works, he conceived the idea of giving the _leading_ part to the _violoncello_, and of throwing the harmony into the violin, alto and bass; the second violoncello, in the mean time, sometimes accompanying the first, and occasionally playing the air in concert with it.”