The pencilina is like an instrument from Dr. Seuss’s The Butter Battle Book. It’s got bass and treble necks with movable bridges and open strings which can be plucked, played with a bow and manipulated with drumsticks. It is mounted with four bells: a fire bell, a doorbell, and two brass telephone ringers.

Bradford Reed, who invented the zither-like instrument as a teenager, initially used pencils to play the strings and tap different areas of the instrument for percussive effects. Principally a drummer, he often sets up kit parts around the pencilina. The resulting sound is orchestral; its big, multiple sounds are well-suited to silent movies.

Together with renowned cellist Jane Scarpantoni, Bradford Reed will perform musical accompaniment to Stuart Patton’s 1916 version of 20,000 Leagues Under the Sea at a screening in the tabernacle in Oak Bluffs next Tuesday.

Chances are you have heard Ms. Scarpantoni’s cello before more than once. A classically trained cellist, she appears on albums by Patti Smith, R.E.M, the Beastie Boys and Ben Folds Five among others.

“Jane’s just totally amazing,” said Mr. Reed of his frequent collaborator, speaking this week from his Brooklyn apartment. “She’s a super-rocking cellist.”

During the silent era, ironically, cinema employed more musicians than most other American industries. Cinemas generally had a permanent pianist and an organist, or an entire orchestra, who would sit at the side of silver screens — the old cinema screens had elements of actual silver to create a highly reflective surface — and play along with the projection.

Perhaps even more so than in today’s cinema, the music was a key element of the moviegoer’s experience. The music reminded you when to laugh, shriek and cry. Not surprisingly, as cinema progressed into feature-length movies, filmmakers began to exert their creative control. In 1915, W.D. Griffiths issued complete photoplay music sheets to movie theatre musicians across the country to accompany The Birth Of A Nation.

Much of the music written to accompany classic silent movies are lost. Mr. Reed, though he doesn’t know what was played over the 20,000 Leagues film when it was released in 1916, can make a fair guess about certain elements.

“There’s stuff with music that works, there are certain things people respond to,” said Mr. Reed, “chords and rhythms that reflect beauty, or tension — the range of emotions. Western harmony is only tweaked slightly with every generation.”

The score is blocked out to a degree and the two have played the score several times. One evening they did shows back to back with a 10-minute intermission. But there is still ample room for improvisation.

The 1916 film was made on a huge budget for the time and features pioneering, expensive underwater photography for the submarine scenes. Based on the 1870 French novel by Jules Verne, 20,000 Leagues tells the story of the search for a huge sea monster, which turns out to be a submarine surreptitiously helmed by outsider and adventurer Captain Nemo. There is death, mayhem, poignancy and a giant squid attack, all of which has to be evoked by live instrumentation, along with the visual footage and an occasional title card.

“It’s modular, sectional, it’s not timed down to seconds,” he said of their approach. “Not having it totally worked out, there’s still room for risk taking. It’s fun and challenging.”

Mr. Reed also plays the electric zither, slide guitar and a range of percussion instruments and is bringing an extra series of bells for his performance Tuesday.

Though he regularly gets together with other instrument makers to compare notes, as it were, Mr. Reed prefers not to get specific about the makings of a pencilina.

“I want other people to make it their own way. I’m still refining it,” he said. There are also elements tailored specifically to Mr. Reed’s ambidextrous requirements. Even so, several musicians have got in touch with Mr. Reed to show off replica pencilinas made to his specifications.

“It’s getting tougher to be a pure cultural artist in New York, everyone has to have a gig,” said Mr. Bradford who for work composes for television and film. He just finished work on Superjail, an animated television comedy series for Adult Swim.

Mr. Bradford says he has always wanted to get into film music.

“I love film, I love music and I love a lot of film music,” he said, citing as favorites such as Ennio Morricone and Quincy Jones. “It doesn’t compare to a lot of the electronic dreck today.”

Bradford Reed and Jane Scarpantoni will also play Che’s Lounge in Vineyard Haven on Monday night.