You have to be buzzed in to enter the Institute Library — an unusual formality in the otherwise casual hullabaloo of Chapel Street, and yet it lends the institution an air of old-timey charm. I press the button, wait for a crackling, and when asked, “What are you here for?” answer honestly: “I’d like to see the books.”

Indeed, you should enter just to take in the library — it’s a fully somatic experience: breathe in the old pages, run your fingers along leather-bound volumes, bask in golden sunlight and linger among words.

But today, I’m on a mission, so I continue upstairs to the gallery that the Institute Library opened over two years ago. Since then the space has hosted a number of exhibitions, organized primarily by writer-turned-curator Stephen Kobasa. The latest one is a collection of drawings titled “Crossing the Line.”

The space itself is spare: four white walls, pictures framed or raw-edged, sitting on the floor or hung several feet above a scuffed red parquet. A few radiators with herbivore teeth, rounded and yellow, grin with their grilles. Outside through the windows is a parking lot with ant-people waving little arms about some issue or another.  You can hear Sterling-style construction work outside, but for the most part the room is silent and well lit.

Two printed gallery guides lie on the table. There are no plaques or labels on the walls, only these papers that identify the surrounding pieces. Later Mr. Kobasa tells me, “I don’t like footnotes,” and I take the lack of guidance to mean I should explore intrepidly: experience without explanation. I pick up the list and begin a slow museum shuffle — triple step, pause, triple step — towards item #1.

As I look around the room, I begin to notice many graphite caterpillars. In Dave Bassine’s untitled drawing, I take the liberty of seeing a handful of charcoal tapeworms, mouths open, body segments collapsing into each other. In Livingston’s acidic “Worms,” large ones lounge around in their striped pink sweaters, suspended in white space. After all, if a line were given a heart and a few gastrointestinal necessities, wouldn’t it most closely resemble those striated critters?

The rest of the pieces have more disciplined worms, lines that have arranged themselves obediently into shapes.

Indeed, the nature-oriented works find lines as they appear in the world, like gentle Euclidean fingerprints in the ground. Lenny Moscowitz’s “Landscape Study” features chunky blobs that subside and uplift into hills, and, in Joan Backes’ “Berlin Series,” ragged gray bands recall magnetic anomalies on the ocean seafloor. In Rick Shaefer’s stunningly rendered “Sugar Maple,” old men’s wrinkles emerge out of inked bark. Kelly Schmidt’s “Bones” is a micro-exhibit of small skeletal bits; I thought I saw a pelvic bone, some vertebrae and a lone hollow scapula.

The portraits and more comprehensive, detailed challenged the primacy of the stroke. Caught up in the whole, I lost sight of the fundamental unit — I could see automobiles, or freckled faces, but the crosshatches were swallowed up by complex layers. I longed for the simple fullness of “Blind Contours of a Lily,” a stunning work that fleshes out petals with black continuous lines.

“Luce Drawing II,” halfway through, made me smile. Pondering, I thought I recognized the outline of a mug with a teabag inside, but I couldn’t be sure. The lines were endearingly crooked, and I was reminded of that favorite children’s activity of “draween” — grabbing pencils in fistfuls and making skirts from triangles and heads from circles and sometimes not drawing the ears or nose because they were blocky.

On an upside-down table at the entrance to the exhibit, there’s a clean, bound guestbook. Inside are yet more lines, wriggling circles, fluid script strokes and straight-angled bends: everyone with their idiosyncratic signature. Downstairs, in a large filing cabinet, there are other autographs, thousands of index cards listing the library’s book collection in a neat, disciplined hand. I remark that the writing looks like calligraphy, thick lines and carefully inked forms. Chelsea, a volunteer with a recent master’s in library science, tells me that there used to be a font for cataloging collections: “Library Hand,” for uniformity in documents.

Over the phone on Wednesday afternoon, Mr. Kobasa tells me, “In our culture, people don’t like to be called on to put imagination to work; they want the blanks filled in.” We demand high definition in pixels; books will soon be enhanced with multimedia. But the Institute Library and this exhibition both stand in defense of the line. Chapbooks and sketches, the Library Hand font and the charcoal silhouette — the white-and-black spaces that our minds color with thoughts.