AMID the civil hush of the New Main San Francisco Public Library, I recently experienced an aspect to writing I’d all but forgotten: noise. It happened in a workspace called the Typewriter Room. Operating the machine that gives the room its name, I struck the “T” key, then the “H” key, and for the first time in at least two decades, I was rewarded with the bracing clackety-clack of analog-era content production.

When the New Main opened in 1996, its boosters touted it as a “high-tech information retrieval center.” So did its critics. It had 300 computer workstations, additional electrical outlets for patrons who brought their own laptops, a sleek and airy layout with sightlines that made it the envy of every high-security prison warden in the land, and apparently, hidden in some low-tech, off-message nook, a Typewriter Room.

When I stumbled across a Web site mention of it a few months ago, I immediately envisioned an enclave where Mark Twain would feel at home. You know, dark-paneled walls, period carpeting, maybe a large, stuffed bird in the corner.

And of course a boxy, aggressively unergonomic typewriter, with a surfeit of levers, spools, guides, knobs, releases, gauges, clamps and keys.