If Bill T. Jones and Arnie Zane -- partners both in dancing and choreography who held forth last night at the Terrace Theater -- set out to prove that one plus one can equal a great deal more than two, they succeeded eminently. While neither of the collaborative works they showed had quite the evocative power of "Sisyphus," the solo Jones performed Tuesday night, this was nonetheless a fresh, pithy and engrossing evening of dance.

Zane is markedly shorter than Jones, but he has much of his collegue's fluency and charisma as a dancer, plus a certain crisp energy of his own.

"Hand Dance (Third Version)," which dates back to 1977, uses a sequence of arm-and-hand slicings, pattings and smoothings as well as other signal-like movements, as a kind of ostinato around which the two dancers improvise various looser embellishments. The work falls somewhere between the intellectual severity of Twyla Tharp's "The Fugue" and the playfulness of Trisha Brown's "accumulation" pieces.

Some of the semaphoric contents of "Hand Dance" spill over into the recent "Blauvelt Mountain: Act i, a Fiction," a longer, richer, but more diffuse opus that is a montage of movement, taped and muttered sound (by Helen L. Thorington) and verbal free association the dancers intermittently engage in. The movement ranges from the chain reactions of contact improvisation to fixed poses that flash by like a slide show. The imagery, however, is less resonant than that of "Sisyphus," and also less clear in direction -- after a time the work becomes a matter of repetitive tail-chasing. dStill, there's more than enough imagination at work here to make one yearn to see Jones and Zane again, soon and often.