I only saw an afro-horn once, and I hardly saw it then. It must have been the summer of 1968 because it was after Hank Dumas got killed. I didn’t know him that well to begin with, and he’d spent a good part of 1967 in St Louis, so he wasn’t around much that winter. But one night we found ourselves sitting next to each other at the filthy bar at Slug’s, listening to the Arkestra and talking about the music. In the break between sets, Hank told me he’d been doing research on esoteric instruments. I knew about some of Sun Ra’s discoveries in that sphere (the Jupiterian flute, the Solar Sound Organ), but Hank was talking about something I’d never heard of: the afro-horn. He’d written about it, he said, but dismissed his effort as “mythopoetic.” “I thought it was just a legend, a tall tale. But the thing is,” he whispered, speaking so softly that I had to lean toward him to hear, “it’s real.”

Hank claimed that the instrument was invented by the ancient Egyptians, who called it the Tun-tet. In the Book of the Dead it’s described as an “instrument to open the mouths of the gods.” Some scholars thought the Tun-tet was just an implement, a kind of crook or staff used in burial rituals, but in fact it was a horn, Hank explained, forged of an extremely rare metal found only in Africa and perhaps South America. No one knew exactly how it was made, and the tuning system remained a mystery. He added that there was supposedly a “hornbook” to accompany each afro-horn. A primer or instruction manual, a treatise on harmony? I wondered whether it would be written in hieroglyphics or in some esoteric musical notation.

Hank didn’t say much more, except to mention that he’d been trying to locate one. He’d never seen an afro-horn, he said, and there were rumored to be only three in existence: one was held in the collection of a museum in Europe and another supposedly guarded jealously by a small indigenous community on the west coast of Mexico. But the third was in New York, having recently entered the possession of the musician Roland Kirk. Or so it was said. Hank swiveled back around on his stool when the band came back out, and we didn’t speak anymore while the Arkestra played. When they finished, the musicians marched through the audience chanting a kind of recessional (the habitual conclusion to their shows), and Hank and a few others in the audience jumped up to join them. He looked back at me briefly, smiling, as he followed them out onto East Third Street, taking up their refrain: “It’s after the end of the world / Don’t you know that yet?” It was the last time I saw him.

Any fan of the music knows that Roland Kirk was a connoisseur of obscure and handmade reed instruments like the manzello (a modified King saxello, itself a modified B-flat soprano saxophone favored in the 1920s by military bands playing mazurkas and pasodobles) and the intimidating-looking stritch (a thick-set Buescher straight E-flat alto with an inverted neck). He gave them nicknames: He called the manzello his “moon zellar” — an instrument to lure the moon underground. “Stritch” suggests a kind of stick, but something more than that; a stick with an itch to stretch its tonal capacities into something broader, richer. And yet perhaps a stitch too far, as well — an instrument pushing beyond itself, leaping to something new but not entirely succeeding. Kirk was a sight to see on the streets of Manhattan: a big blind man lugging a felled forest of burnished horns behind him in a green golf cart. Onstage he’d drape a menagerie around his neck — not only tenor but also manzello and stritch, which he would play simultaneously and in harmony. These were augmented by a variety of other props: a transversal flute, a nose flute, an oven timer, various sirens and whistles, amulets and necklaces.

When Dumas died so suddenly that spring, I felt — as another young writer striving to find ways that language could approach this music — that it was somehow my responsibility to continue his research. I went up to Kirk after a show at the Vanguard, approaching him as he packed up his horns in the narrow hallway back by the bathroom. I’d met him once or twice, but I had no idea how he’d react to my inquiry. Bent over, he stopped moving when I said the word “afro-horn.” He didn’t peer up at me, of course, but instead almost listened up quizzically at me, as though he were gauging the sound of my intentions even after I’d stopped speaking. Finally, he said in a gruff voice that I’d have to come to his place. “Right now?” I asked. But he’d gone back to packing his horns. So I waited out front by the stairs leading up to Seventh Avenue.

When we left together, Kirk began talking. He made no effort to engage me in conversation, nor did he ask why I was interested. It was as though the word itself were talisman enough to bring me into a circle of familiarity.

Kirk told me that he’d been given an afro-horn by a vagabond who had been a common sight on the streets of the Village. I remembered him. He called himself Aulos and fashioned himself a sort of amateur archivist of diasporic arcana. He walked around pushing a shopping cart laden with piles of what looked like rags and useless objects. Most people walked right by him without a second glance. But every once in a while, he would stop a passerby. Never a white person. He would walk right up in a manner that couldn’t be ignored or evaded, always to offer a gift, as though he had a special delivery in the cart that he’d been waiting patiently to give to just that person. It would be a small thing, but something with some unusual aura or oblique relevance. One day on Bleecker, I saw him give a deck of cards he said had belonged to the magician Black Herman to a man who, after a brief double take, admitted he was a professional gambler. I heard that Aulos once surprised the trumpeter Lee Morgan near Cooper Square with a rusted cornet valve that he claimed had graced Buddy Bolden’s horn. Aulos came up to me only one time, back when I was trying to write about what I called the unsung heroes of Pan-Africanism, and pulled out a yellowed issue of Dusé Mohamed Ali’s newspaper African Times and Orient Review from 1913, with articles by Marcus Garvey and George Bernard Shaw. He turned away before I had a chance to thank him properly. Reading that paper opened up a whole new direction in my research.

When we reached Kirk’s apartment, he didn’t turn on the lights. I’d heard that he often went around his place in the dark and was in the habit of listening to music that way. It’s perfectly logical, when you think about it — what difference does it make to a blind man? But it was something to be sitting there in a room lit only by the moon and by street-lamps and slowly come to realize that the afro-horn he was telling me about was right there in the room with us.

Kirk spoke to me for hours about the reasons he couldn’t or wouldn’t play the afro-horn. I didn’t follow all of it. Any reed instrument is another voice, not your own, he told me. The reed itself, even before it’s in the saxophone, is an “ersatz tongue,” and if you paid enough attention you could hear its accent. Once, while in the South of France to play a festival, he’d made a pilgrimage to the cane fields outside Fréjus, where the great majority of saxophone reeds are still made. Uncut tongues hum in the wind around you like a nasal Mediterranean language you don’t know but almost understand, he said; you smell the sea, but you can’t hear it. So to put your mouth to a horn is to wrestle with another mouth, a distant way of speaking. You know what the French call the bell of an instrument? he asked. They call it a pavillon, from the Latin for “butterfly”: something takes flight when your horn talks, the sides of a tent flirting with the breeze.

“There is thunder in that bell,” Kirk said, pointing at a bundle in the moonlit corner of the room. “Hungry, always hungry.” I stared at it but didn’t dare go over. It was not in an instrument case but a kind of misshapen bag, possibly made of felt or canvas. The bag bulged with sharp and irregular protrusions. It was partially open at the top, and a bit of metal was visible. It didn’t look like a saxophone, at least not any sort I’d ever seen. It wasn’t shaped right, for one thing. It was bigger, and it wasn’t clear where you would put your mouth, and it looked like there were too many keys. It almost looked like one of those nkisi nkondi protective statues from the Congo, a kind of animalistic shape covered with dozens of nails and tacks driven into its body. As though each hand that touched it would have to find its own fingering in a treacherous thicket of thorns.

The problem with playing the horn wasn’t actually a technical one, Kirk explained. It was above all a matter of what he called the “danger of extensions.” Hank had used the same term; I thought he just meant the overtones present in any sound wave. But it meant something more. I remembered something Kirk had said a few hours earlier to the crowd at the Vanguard, explaining the effect when he played two horns at once: “It’s splitting the mind in two parts. It’s like making one part of your mind say, ‘Oo-bla-di,’ and the other part of your mind say, ‘What does he mean?’” Extensions have to do with the coexistence of frames of reference. Sound, more powerfully than any other sense, could transport you to Fréjus or to Fez. And that effect, Kirk went on, was immensely powerful; if it could bring people together around a shared but submerged register of vibration, it could also overwhelm a listener for whom a given frame was impossibly alien. This overwhelming could even be physical. Many years later I found a phrase for it in an essay Amiri Baraka wrote about Hank Dumas: black music is forceful because it makes the whole body “a field of sonic ideational penetration.”

Kirk said he’d only taken the afro-horn with him to a club once. He didn’t even take it out of the bag, but a woman sitting next to the stage became violently ill during the concert just from the sympathetic vibrations of the afro-horn as he played the stritch. Since then, he’d kept it in the bag at home, he said. He added that he wanted to give the afro-horn to Albert Ayler, the one musician who might know how to handle its power.

I don’t know whether he ever had the chance to do so. After Kirk passed in 1977, I asked musicians who were close to him if they’d heard tell of the instrument among his possessions, but I got only blank stares. A few years ago, I made a trip to Paris after finding what I thought might be a reference to another of the afro-horns in the online catalog of the Musée de l’Homme. A polite archivist, overlooking my poor French and the strangeness of my request, agreed to fetch the relevant box but came back from the stacks empty-handed. Introuvable, she shrugged, possibly lost or misplaced or stolen over the years.

In the winter of 1970, after Ayler’s body turned up in the East River, I used to go to the Congress Street Pier in Brooklyn and look out into the harbor. I suppose it was a morbid pilgrimage of sorts, to go to the place where the waters had delivered him and stand there listening out into the distance. Once, looking into the flotsam and muck beneath the dock, I saw a book floating in the water, an elementary school English textbook. Jettisoned primer, waterlogged tongue. The sky was dark, and I heard a rumbling far away, but it hadn’t started raining yet. Words came into my head, a quotation the source of which I couldn’t recall to save my life. Seal up what the seven thunders have said, and do not write it down.