By producing Handel's "Acis and Galatea" and Purcell's "Dido and Aeneas," the Lowell House Musical Society has properly challenged the unjustified away of the ponderous 19th century opera. Last night's "Dido" makes you think that opera would be better off if everyone did as much with older works as Lowell House has.

Adele Milheudler's performance of the heroine is a calculated unity of good singing and deliberate acting that makes "music drama" intelligible. She involves her face and her body in the sense of what she is saying rather than in the mere mechanics of articulation.

The part of Aeneas makes the best use of James Perrin's good voice. Ruth Beaver, who stepped in to sing Belinda at the last minute, and Anna Shackford make their duct, "Fear no danger to ensue," the loveliest aria of all. Malcolm Holmes has unusual success in getting the very most out of his able orchestra and chorus. Most exciting of all is Judith Haskell's choreography.

Against the delicacy of the music and the action, the costumes and set are pretentious. The complexity of lighting and props, from which "Acis" was so happily free last year, provides mostly darkness and detours.

The lucky people who have all the tickets for tonight's performance should savor it before the Metropolitan dumps the 19th century on them next week.