Have you ever encountered an entirely new landscape or situation and simultaneously noticed that you don’t have the words to describe it or to ask questions about it? It’s not that you’ve forgotten the words or have suddenly regressed to a state of preverbal babbling, you realize, but that you’ve found a corner of experience that is still remote to you, a forest still overgrown with your own ignorance - your "unknown unknowns" have waxed into "known unknowns," and the effect has left you speechless.

Pretend you’re on your brother’s sailboat, watching your brother race around tying knots. "Why do you keep moving that big horizontal stick around?" you ask.

"It’s called the boom," your brother says.

"What’s the difference between the little sail and the big sail and what’s that you’re tying the little sail to?"

"The little sail is the jib; the big sail is the mainsail; I’m tying the jib to the winch," he replies, efficient as flash cards.

Pretend now that you’re reading Homer and you want to know what a Greek trireme would’ve looked like and where the oarsmen would‘ve sat, or you’re writing a story set in a Gothic cathedral and you need to describe the interior where the exorcism is taking place, or you’re going to the theater and you want to know the layout of a modern orchestra pit. Or pretend you’re just really, really curious. Or a little eccentric.

I bet you would like visual dictionaries, or picture dictionaries, as our library catalog likes to call them. These books diagram and label (oftentimes in multiple languages) the objects that make up our world: animal, vegetable, mineral, and synthetic. Some are historical, some deal in specific fields (physics, architecture), and some break down the components of an object that on the surface seems simple, showing the whole in context and then extracting the pieces, naming parts you didn’t even know had names. Who knew there could be 33 parts to an umbrella? Or that the end of a curtain rod is called a "finial"? Many of these books are aimed at juvenile readers, but many more go into a fascinating level of technical detail that might come in handy when you’re trying to have an intelligent conversation with your car mechanic or your piano tuner or your bartender.

The novelist Ian McEwan once reminisced in an interview about an era of writers now passed who really knew the names of things, likening Philip Roth and others to nineteenth-century novelists Flaubert and Tolstoy, who named "bits of furniture and bushes in the garden; they [knew] the names of corners of eaves and bits of building." The amount of verisimilitude a technical word can lend a work of fiction is perhaps a matter of opinion, and technical words can be over-used (at which point we refer to them as jargon), but I think there’s something to Ian McEwan’s wistful information-hunger. By slicing to the heart of the matter, the naming of an object can sometimes do the opposite of what you’d expect: it can open up the mystery of the moment. Somehow a room full of chairs feels a little different than a room full of cabriole chairs. Think of bright, blooming cumulus clouds, or the first time you ever heard the phrase "flying buttress." The word can evoke so much more than our literal mental image of the thing. I wonder how much poetry has been written about Corinthian columns alone.

Just like anything else, visual dictionaries are artifacts of their time and place, so if you want to remember or discover what was important back when, flip through the Newnes Pictorial Dictionary from 1960 and check out their chart of U.S. and Russian satellites. Or watch the aesthetic changes in everything from clothing to camping equipment (old department store ads are good for this too). I’ve been leafing through The Visual Dictionary of Everyday Things, published by Dorling Kindersley in 1991, and the recent past comes to feel more distant when I consider how dearly we held portable cassette players and mini-televisions. And yet... somehow the Walkman’s dull yellow plastic can bring back middle-school to me in a Proustian rush.

And I suppose if you’re not into the technical names of things, there’s always metaphor.