The Thump Keg Mystery
Dr. G. G. Wilkins explains why a second chamber knocking between the pot and the worm turns one run into nearly two, going back to the old Pennsylvania rye men and Samuel M'Harry's 1809 distilling book. He tells how a Concord assistant assessor hid inside an empty doubler barrel, and how Barnaby rolled it down to the turnpike and bit out a piece of the man's backside. Blue Ridge herbalist Clara Higgins tells about thunderstorm runs, a chestnut-log doubler that blew its hoop, and a persimmon-charged thumper. Wilkins then answers Cletus 'Rabbit' Miller of Wilkesboro, NC, on whether hickory ashes and red oak shavings in a thump keg do any good, and knocks down the myth that a louder thump means stronger spirit.
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Full episode transcript
♦ Audible wax cylinder surface crackle, slow drip of clear distillate into a glass jar
♦ Barnaby the black bear grunting and chain clinking outside log cabin window
Wilkins: Barnaby! Barnaby, you hairy sack of sin, settle yourself down! You've had a whole pail of mash-bottoms and half a woodchuck since supper. Lie down before I come out there and pull every tooth in your head with my blacksmith's tongs. [SOUND: Bear grunt, chain drops into the dirt] There. Friends, that's the evening's run dripping in the jar, and the other noise is four hundred pounds of bad manners wearing a chain.
♪ 1860s parlor banjo and mountain fiddle theme with antique warmth, swells and fades under
Wilkins: Good evening, neighbors, and welcome to Radio Moonshine with Alchemist G. G. Wilkins, broadcasting from the log walls of Fort Wilkins on the Suncook Valley Turnpike, Route 28, in Pittsfield, Merrimack County, New Hampshire. I'm Dr. George G. Wilkins: dentist, blacksmith, inventor, stamper of coin, and twice the guest of the Merrimack County sheriff, who keeps a chair warm for me the way some men keep one warm for their mother-in-law. Tonight's subject is one that's knocked on my door for thirty years. I mean that literally. It knocks. We're talking about the Thump Keg Mystery: why a second chamber, set between the pot and the worm, makes a better drink.
Wilkins: Before we start, a word from the folks who keep the copper bright in this valley.
Announcer: Friends! A quick word! The Flame-Flow Still, protected under United States Patent 10,561,960, is hand-built of heavy-gauge pure copper for the honest craftsman. See it at moonshinestill.com, or stop by the Fort Wilkins showroom on Route 28 in Pittsfield!
♪ Short fiddle sting
♦ Wax cylinder crackle
Wilkins: Segment the first: history. The first time I ever heard a thump keg I was a boy of about eleven, delivering horseshoe nails to a cooper over in Barnstead. It was a warm night, the door was propped open, and from the back of that shop came a sound like a big man knocking at a door. Thump. Thump. Thump. I thought the sheriff had learned to knock politely, and that frightened me worse than any warrant. The cooper laughed so hard he swallowed his chaw, and it took him a quarter hour of coughing to bring it back up and explain.
Wilkins: Here's the nature of the beast. A common pot still is a kettle with a lid and a pipe. You boil your fermented wash, the vapor rises, runs down the pipe into a copper worm sitting in cold water, turns back to liquid, and drips into your jar. But one trip through a plain pot doesn't give you much. The first run comes off weak, cloudy, and coarse. The old Scotch and Irish distillers called it low wines, and they ran it through the still a second time to bring it up to strength and sweetness. Two runs means two firings, two days, and two cords of wood you split with your own blistered hands.
Wilkins: Then some clever devil, and I'd love to shake his hand and check his teeth, set a second vessel between the pot and the worm. Hot vapor from the pot goes down a pipe that runs nearly to the bottom of that second keg and bubbles up through whatever liquid is waiting there. At first the liquid's cool, so the vapor bubbles collapse with a knock. Thump. That's your name. As the keg heats up, the liquid inside comes to a boil, and the knocking settles into a low, contented rumble, like Barnaby after a ham. Now the vapor leaving the top of that keg has been boiled a second time, and it's stronger and cleaner for it. One firing gets you close to what two used to. The old Pennsylvania rye men called the first spirit singlings and the second doublings, so the keg got the name the doubler. In the mountains they call it the thumper. In my house it's that damned keg, because I've barked my shin on it more times than I've barked at the tax man.
Wilkins: The Pennsylvania farm distillers out on the rye country knew this business well. There was a book printed in Pennsylvania in 1809 by one Samuel M'Harry, called The Practical Distiller, one of the first distilling books ever printed in this country. I've got a water-stained copy on the shelf behind me with a molar pressed in it for a bookmark. Don't ask whose molar. He didn't need it anymore, and he paid for the extraction in rye. M'Harry wrote for farmers, plain men who wanted their grain turned into something that would travel over bad roads and fetch a fair price. That's the whole point of the doubler: more strength out of less fire and less labor.
Wilkins: A pot still without a doubler is like a man with one boot. He'll get there, but he'll get there slow, and he'll complain the whole way.
♦ Barnaby grunts, chain rattles
Wilkins: Barnaby agrees. Barnaby likes a thump keg because it's the only thing on this farm that knocks before it comes in.
♪ Banjo bridge, quick and rascally
♦ Wax cylinder crackle
Wilkins: Segment the second: legends, outlaws, and a fool in a barrel. Last autumn an assistant assessor came out from Concord, a narrow, damp sort of fellow with a nose like a pickaxe and a measuring tape he wore around his neck like a bishop's stole. He'd been sent to measure my apparatus. I told him plenty of ladies in Pittsfield had tried to measure my apparatus and none of them came back with a satisfactory figure. He didn't laugh. Concord men don't. They have it pulled out of them at birth along with the cord.
Wilkins: Now, I had an empty doubler barrel sitting out by the woodpile, a good oak keg, staves an inch thick, waiting on a new hoop. And Barnaby, God bless his rotten heart, had been working at his chain staple all week the way a boy works at a loose tooth. Right as Mr. Assessor bent over to read the mark on my pot, that staple let go with a pop like a champagne cork. [SOUND: Chain whipping loose, a deep bear huff] That bear came round the corner of the still-house at a lope, and the assessor did the only intelligent thing he ever did in his life: he dove headfirst into the empty doubler barrel. Tape, hat, and all.
Wilkins: Barnaby had never seen a barrel that squeaked before. He sniffed the open end, got a noseful of government man, and gave it a nudge. That barrel rolled. We're on a slope here, friends, and it rolled right down toward the turnpike with the assessor inside going round like a pickled egg in a churn. I could hear him every turn: Oh! God! Oh! Lord! Oh! Mother! And Barnaby galloping alongside batting it with his paw like a cat with a spool of thread.
Wilkins: It fetched up against the stone wall at the bottom of the hill with a bang that cracked two staves open. Barnaby stuck his great snout in through the split, found the softest thing in the barrel, and bit. I heard it from the top of the hill: a wet, tearing sound, like pulling your boot out of April mud, followed by a scream that set the Haddock boys' cows bawling a mile off. When I got Barnaby back on the chain with a ham hock and a few words I won't say in front of your grandmother, I tipped the barrel up. Out came the assessor, white as lard, with blood running down into his left boot and a piece of his britches the size of a dinner plate gone missing, along with about a pound of what was underneath them. The assessor came out of that barrel with his dignity behind him, and Barnaby had eaten most of it.
Wilkins: I laid him face-down across my anvil bench, poured raw spirit over the wound while he cussed in two languages and invented a third, and stitched him up with horsehair and a harness needle. Eleven stitches. I told him it was the first federal property I ever handled with any tenderness. He had a loose bicuspid rattling around from the ride down the hill, so I pulled that free of charge. Then I paid his livery bill with a handful of my stamped coppers, G. G. WILKINS, PITTSFIELD N.H., struck right on that anvil. Never did measure my still. That was a pound of federal rump Barnaby ate, and I reckon it's the first time the government ever fed anybody in Merrimack County.
♦ Barnaby grunts contentedly
Wilkins: Don't you look proud, you tub of grease. Now, folks, I've got a guest tonight who came a long way up the road from the Blue Ridge of Virginia, through the ruin of that country since the war, to sit in my drafty log house and drink my coffee, which I warned her is worse than my whiskey. She's a mountain herbalist and a keeper of the old words for spirit. Please welcome Miss Clara Higgins.
Clara: Evenin', Doctor. I'll tell you straight, I've had worse coffee, but it was in a Lynchburg jail and the sheriff made it out of acorns and spite.
Wilkins: Ha! She's been in the jailhouse. I knew I'd like you. Clara, you've got a tongue sharper than my forceps and a good deal more popular with the patients.
Clara: That's 'cause my tongue don't charge a dollar a tooth, Doctor. Now, you up here in New Hampshire talk like every word costs you a penny.
Wilkins: Up here we do pay by the word, madam. Ask any lawyer in Concord. Tell me about the thumper in your country. Down there in the Blue Ridge it's practically a member of the family, I hear.
Clara: Oh, it's the heartbeat of the holler. But that heartbeat's a tattletale, Doctor. On a still night you can hear a thumper knocking a mile up a hollow. The revenue men learned to just stand on a ridge in the dark and listen. So my granddaddy's people only ran on summer nights when a thunderstorm was rolling over the mountain. Lightning cracking, rain coming down like the Lord kicked over a bucket, and that thumper going thump, thump, thump right under the thunder where nobody could tell the one from the other. They called what came off those nights storm whiskey, and they swore it had a little lightning in it.
Wilkins: Running a still in a lightning storm. That's either genius or the kind of stupid that gets you a short sermon and a long box.
Clara: Little of both, and Uncle Royal got a taste of the long box. Not from lightning, though. From his doubler. He'd hollowed out a chestnut log, big around as a rain barrel, and banded it with green hickory hoops he bent himself. Called it the old drum. Ran it for years. Then one night the mash foamed up in the pot, puked over, and plugged the line with a gob of hot slop. Nobody was watching close enough. The pressure built and built in that chestnut drum till it let go with a bang like a field cannon. A hickory hoop shot across the holler, whistling, and buried itself in a sourwood tree a good forty feet off. Royal was sitting about two foot left of where it flew. It took the end off his ear neat as a pair of shears, and he bled down his shirt like a stuck hog.
Wilkins: Two feet to the right and they'd have buried him with a barrel hoop for a necktie.
Clara: That's what Mama said. That hoop stayed in that sourwood for twenty years. Every boy in the family got walked down there at fourteen and shown it. That's what happens when your line's shut, they'd tell him. A thumper's got to breathe.
Wilkins: God's truth, and I'll preach it louder in a bit. Tell me about the words, Clara. I want my listeners speaking proper mountain.
Clara: Well, you've got your thumper and your doubler, same animal. When the mash boils over into the line, that's the puke, and you don't want it. Some folks set a little box or keg between the pot and the thumper to catch it, and that's a slobber box. The first run's singlings, the second's doublings. And a man who's had too much of the doublings, we say he's been kicked by the thumper.
Wilkins: I've been kicked by the thumper so often I walk with a list to the left.
Clara: I noticed that when you came out to the wagon. I figured it was the bear.
Wilkins: The bear's the right side. Now I'm told your people put more in a thump keg than plain wash.
Clara: My great-uncle Asa did. In the fall he'd wait till after the first two or three hard frosts, when the wild persimmons turned soft and wrinkled and sweet as sorghum, and he'd mash a bushel of 'em into his thumper. The hot vapor bubbled up through all that fruit and carried the flavor out the top. Came out soft and golden-tasting, a little like honey and a little like a Christmas pudding. The neighbors called it possum sugar, 'cause the possums go crazy for persimmons and so did every deacon in the county.
Wilkins: Why after the frost?
Clara: Doctor, have you never bit a green persimmon? It'll pull your mouth shut tighter than a miser's purse. My cousin Jubal was too impatient one year and threw green ones in the thumper. That spirit was so puckery that the preacher took a nip on Saturday night for his throat, and Sunday morning he got halfway through the sermon on the prodigal son and his mouth drew up like a drawstring bag. He stood there in the pulpit going mm-mm-mm, red as a beet, waving his Bible. Finally he just sat down.
Wilkins: What happened to the prodigal son?
Clara: Nobody ever found out. The congregation called it the finest service they'd sat through in thirty years.
Wilkins: Ha! Clara Higgins, ladies and gentlemen. Stay at the table, Clara. I've got a call-in tape later and I'll want a mountain witness.
Clara: I'll stay, long as the bear does too. I'm not sure which one of you I trust less.
Wilkins: Trust the bear. He's honest about wanting to eat you.
♪ Fiddle sting into a rollicking banjo vamp
♦ Wax cylinder crackle
Announcer: Step right up, friends of the copper and the flame! Are you weary of tin pots that taint, scrap-iron kettles that reek of sulfur, and soldered seams you wouldn't trust with your mother's soup? Then hear me now! If you appreciate authentic American craftsmanship, look no further than Moonshine Stills, proud home of the Flame-Flow Still, the flagship of the line, protected under United States Patent 10,561,960! Built of heavy-gauge, high-purity electrolytic copper, refined pure and bright, and joined with precision CNC-machined brass unions. Every seam is true, and there's no lead to poison your parlor! The Flame-Flow is engineered to maximize convective circulation, so the heat rolls even and the vapor runs clean, giving unmatched purity for essential oils, herbal tinctures, and traditional distillation demonstrations. A handsome, gleaming copper heirloom for eight hundred and ninety-nine dollars! Stop by the showroom at Fort Wilkins on Route 28 in Pittsfield, New Hampshire, where the bear will see you in. Or order direct at moonshinestill.com/products/flame-flow-copper-still! Once more, friends: moonshinestill.com/products/flame-flow-copper-still! The Flame-Flow Still, copper you'll hand down to your grandchildren!
♪ Banjo flourish and button
♦ Wax cylinder crackle, drip into jar
Wilkins: Segment the third: copper and the craft. Now I'll teach you how a thump keg is laid out and run, step by step, so you understand it right. Everything on this program is history and instruction. Making spirits to drink without a federal license is against the law of this nation, and I've got two arrests and a bear to prove the government means it.
Wilkins: Step one: the train. From the fire you have the pot. From the pot's cap, a copper line runs to your slobber box if you keep one, which I recommend. From there, a line runs into the doubler. That inlet pipe has to reach down nearly to the bottom of the keg so the vapor bubbles up through the charge. From the top of the doubler, above the liquid, an outlet pipe runs to your worm, coiled down in a flake stand of cold running water. The worm's tail runs out to your jar. And mark me: that worm's end is open to the air. The whole train must breathe from pot to jar. Seal the joints tight against leaks, but never stop up the passage. A thump keg sealed tight is not a distilling apparatus, it's a Fourth of July cannon pointed at your own britches. Ask Clara's Uncle Royal and his short ear.
Clara: He'd tell you, if he could hear you on that side.
Wilkins: Step two: charging the pot. Fill it with fermented wash, but no more than about three-quarters full. Wash foams as it comes to a boil, and if you've filled it to the lip it'll puke straight into your line. That's where a plug starts, and a plug is where a burst starts.
Wilkins: Step three: charging the doubler. Fill it a quarter to a third full. Some use plain wash. Thrifty men use the tails they saved from the last run, the weak, oily end of the spirit, because the doubler boils the good alcohol back out of them and you waste nothing. Clara's people use frost-ripe persimmons for flavor, and an apple man up here might use cider pomace. More than a third full and the vapor has too much to push through, the keg gets sluggish, and you're more likely to carry liquid over into the worm.
Wilkins: Step four: the fire. Low and steady, friends. Dry hardwood, split even. You're not shoeing a horse, you're coaxing a kettle. As the pot heats, vapor reaches the doubler and the knocking starts. Thump. Thump. That's cool liquid swallowing hot vapor. Let it work. When the doubler's charge reaches a boil, the knock eases to a rumble and the spirit starts coming out of the worm, and it comes out stronger than a plain pot would ever give you on a first run.
Wilkins: Step five, and this is where men go blind and die: the cuts. A doubler does not excuse you from the cuts. If anything, it makes them come on faster, because that first spirit rushes out strong. The first trickle is foreshots. Throw it out, every drop. It's harsh, poison stuff, and it isn't fit for drinking, for rinsing a tooth socket, or for cleaning a dead man's boots. Next come the heads, sharp-smelling, like a varnish pot. Catch those in a row of small jars, never one big crock, so you can sniff each one and tell where the heads end and the hearts begin. Hearts are your clean, sweet middle, what you were after all along. When it turns oily, dull, and wet-dog-smelling, those are the tails. Set them aside for the next doubler charge. Small jars, honest nose, no greed. A greedy distiller and a greedy dentist have killed about the same number of men, and I've known both.
Wilkins: Step six: the copper. A copper doubler and copper line give the vapor more copper surface to touch on its way to the worm, which works on the sulfur stink. So the doubler sweetens the spirit two ways: once by boiling it a second time, once by copper. And keep a sharp eye on every joint. Alcohol vapor is flammable as a widow's temper. A pinhole leak near an open fire and your still-house goes up like a Fourth of July bonfire with you in it. Never walk away from a running still. Not for dinner, not for the privy, not to admire the moon, and not to chase a bear.
♦ Barnaby grunts, chain clinks
Wilkins: He knows I'm talking about him. Step seven: when the run is done, let the fire die, let everything cool, then empty the pot and the doubler and scrub the copper bright. That's the whole mystery of the thump keg, neighbors: a second boil in a single firing, a heartbeat between the kettle and the worm.
♪ Slow fiddle air, warm and scratchy
♦ Wax cylinder crackle
Wilkins: Segment the fourth: myths, slang, and the mail bag. We've got a call-in tape, and Clara's still here as a mountain witness. Roll it, boy.
♦ Phonograph cylinder clicks in, hiss and crackle
Cletus: Alchemist, my uncle swears old-timers used to throw hickory ashes or red oak shavings into the thump keg to clean out bad heads. Is there any truth to that, or was he just making swamp medicine?
♦ Cylinder clicks off
Wilkins: Cletus Rabbit Miller, of Wilkesboro, North Carolina! Wilkesboro and Wilkins. I reckon we're cousins by spelling, and you're the cousin who got the better weather. Let me answer you properly, and I'll strike a coin for you while I do.
♦ Steel punch clangs on copper coin
Wilkins: First, the ashes. Hickory ash is a fine thing in its place, and its place is the soap kettle. Pour water through ash, catch what drips out, and you've got lye. Potash. My mother made soap with it every spring and it took the skin off my knuckles every Saturday night. Throw a fist of hickory ash into a hot thump keg full of mash that's got corn oil and sour acids in it, and you know what you get? Foam. Soapy, slippery, caustic foam boiling up in your doubler. Your uncle's grandpappy saw that foam rising and thought he was scrubbing the devil out. Rabbit, your uncle didn't invent a cure, he invented soap, and he invented it in the one place nobody wants to wash. Lye does nothing for bad heads. The only cure for bad heads is the cut: catch them, smell them, and set them aside.
Clara: We had a fellow on Buffalo Ridge did the ash trick. His spirit tasted like he'd strained it through a wash-day apron. Folks called it Monday whiskey.
Wilkins: Monday whiskey! I'm keeping that. Now the red oak, Cletus. There's a grain of truth in it, and I mean grain. Oak gives up tannin and color, the very thing that turns spirit amber and mellow when it rests in an oak barrel. Toss oak shavings in your thump keg and you'll get a little woody flavor riding along with the vapor, and a man might swear his spirit came out smoother. But that's flavor, not cleaning. If an old-timer wanted color and oak taste, he'd set a few charred oak chips in the finished jar and let them steep for a season. That works. Shavings in the doubler is a carpenter's guess at a chemist's job.
♦ Steel punch clangs on copper coin
Wilkins: There's your coin, Rabbit. G. G. WILKINS, PITTSFIELD N.H., struck while I answered you, and it's yours if you ever find your way up the turnpike. Bring your uncle. I'll pull a tooth for him at half price if he promises to keep the soap out of his keg.
Wilkins: Now a myth for the whole valley. The louder the thump, the stronger the shine. I've heard it in every tavern from Epsom to Barnstead. Hogwash. How loud a thump keg knocks depends on how hot your fire is, how deep your charge is, and how cool the keg still is. A cold keg with a big charge and a roaring fire will knock like a jackass kicking a stall door, and the spirit coming out could be weak as dishwater, or it could be full of heads because you ran it too hot and fast. A loud thumper proves your fire is hot, the same way a loud preacher proves his lungs are sound, and it tells you nothing about the quality of either one's spirit.
♦ Steel punch clangs on copper coin
Wilkins: And here's a second myth that's killed men: seal the thump keg tight to build pressure and you'll get stronger spirit. No, you'll get a funeral. Pressure doesn't make proof. Pressure makes shrapnel. Clara?
Clara: Forty feet, into a sourwood tree. That's all I'll say.
Wilkins: That's all that needs saying.
♪ Banjo and fiddle reprise, soft
Wilkins: Before we close, a word from our friends at the copper works.
Announcer: One more quick word, friends! The Flame-Flow Still, United States Patent 10,561,960, built of heavy-gauge electrolytic copper with brass unions. See it at moonshinestill.com, or visit the Fort Wilkins showroom on Route 28 in Pittsfield!
♦ Wax cylinder crackle
Wilkins: Neighbors, if tonight's knocking has stirred your curiosity, enroll in the Alchemist G. G. Wilkins Distilling Course. I'll teach you the history, the copper, the cuts, the fire, and the honest law of it, at my own bench, with my own burns to show for every lesson. Ask after it at the Fort Wilkins showroom on the Suncook Valley Turnpike. Barnaby will greet you at the gate, and if you bring him a ham bone he may even let you keep both cheeks.
Wilkins: Many thanks to Miss Clara Higgins of the Blue Ridge, who came a long way to insult my coffee and improve my vocabulary.
Clara: Thank you, Doctor. Next time, I'm bringing the coffee and you're bringing your manners. We'll see which one of us shows up empty-handed.
Wilkins: You'll win that wager. And to Cletus Rabbit Miller of Wilkesboro: thank your uncle for the question and keep the hickory ash where it belongs, in the soap kettle. Keep your copper clean, your cuts honest, and your fire low. Goodnight from Fort Wilkins.
♪ 1860s parlor banjo and mountain fiddle theme, rising then fading
♦ Bear grunt and final drip into jar