Last Friday's Symphony concert dramatized for the music-lovers of Boston the essentially two-sided nature of their famous orchestra--its superb accomplishments in certain fields and at the same time its doubtful musical taste, unchangingly puzzling from year to year.

Concertmaster Richard Burgin, who filled in for Koussevitsky last week, started his program with what proved to be a prime example of the Symphony's doubtful taste. He chose what should have been a musical treat, a Handel Concerto Grosso in D Minor; but he treated it with bombast instead of finesse, using a huge orchestra that included among other things ten double-basses to play something written for a tiny group of strings. Performed in that fashion, the Concerto lost all of the finesse and delicacy which make it a great work.

Again in the second number on the program Burgin displayed what seemed to many like peculiar musical taste, this time in his choice of the work rather than its performance. A Divertimento by Alexai Haieff, a young Russian-born composer now living in the United States, was the composition; its value seemed to many in the audience extremely limited. It is dangerous to condemn a new work too quickly, but this seemed at first hearing to be nothing more than inferior theatrical background music which might have been used for "On the Town." Why Burgin chose to play it is a mystery typical of the whole in-and-out tradition of the Boston Symphony.

The second half of the Friday program showed the Symphony on its brighter side, thus completing the puzzle for the audience. In the suite from the Prokofieff ballet "Chout", Burgin had chosen something off the beaten track but at the same time eminently worthwhile and interesting. The suite catches amazingly well the comic characteristics of this very humorous ballet, written by the man who must be considered the leading humorist among the world's composers. Burgin's interpretation added considerably to the effect. Here he had displayed originality of choice and accomplished performance at once.

Originality was lacking in the final work performed last Friday, but not accomplishment. Burgin, following the lead of Koussevitzky, gave Sibelins' First Symphony a performance which made the frequently-performed opus dramatically effective to a point few would have considered possible, thus bringing the bewilderment of the audience to full circle. Just what makes the Boston Symphony what it is will probably never be known; all you can hope when you go to a concert is that you hit them on the upswing of taste and performance.