IThe Instrument
A pendulum is the simplest machine that can keep time, and the second simplest that can tell a lie. Hang any weight on any thread and it will swing with a period that depends on nothing but the length of the thread and the pull of the earth: twenty centimetres of chain, nine-tenths of a second, no matter what hangs at the end, no matter who holds the top. Galileo noticed this in the cathedral at Pisa watching a lamp; Huygens built a clock on it; and for the four centuries since, the same instrument has hung from the fingers of miners, priests, physicians, midwives, soldiers, and the merely curious, who asked it questions and watched it answer.
What it answers with is motion. Held still, a pendulum stays still. Held by a living hand it does not, because a living hand is never still: the pulse, the tremor of the small muscles of the fingers, the breath, the slow drift of a raised arm all move the point of suspension by fractions of a millimetre, and a pendulum is a resonator. Push it at its own frequency, however slightly, and it gathers the pushes and turns them into a swing you can see across a room. This is the same physics that lets a child on a swing go higher with small kicks made at the right moment, and it is why a pendulum in the hand always, eventually, does something.
The question, then, is not whether the pendulum moves but what moves it. The tradition’s answer is that it moves in reply to something outside the holder: water under the ground, ore, a lost ring, a sickness, a truth. The other answer was given, more carefully than anyone before or since, by a French chemist in 1833.
Michel-Eugène Chevreul, the man who discovered margarine and explained why colours change beside one another, had been playing with what was then called the pendule explorateur: a ring on a thread, held over a dish of mercury, which was said to swing in one manner over metals and another over water. It did. Chevreul, being Chevreul, then put a sheet of glass between ring and mercury, and the swinging weakened. He blindfolded himself, and it stopped. He rested his arm on a support, and it stopped. He concluded that the pendulum was moved by his own muscles, that the movement was real and involuntary, and that it was governed by his expectation: he moved the ring because he believed it would move, and he did not know he was doing it. He wrote it up in a letter to Ampère, and twenty years later, when the same phenomenon filled the drawing-rooms of Europe as table-turning, he expanded it into a book. The English physiologist William Carpenter gave the effect its name in 1852: ideo-motor, an idea that moves.
I build pendulum boards, and I have no interest in pretending Chevreul was wrong. He was right, and his being right is the reason the pendulum is worth a lifetime’s attention rather than an afternoon’s. Consider what he actually found: a hand that answers questions the mind has not consciously asked, and answers them in a language the mind cannot consciously fake. The pendulum is a lever on the self, a stethoscope held to the part of you that already knows what you want, already noticed the detail you overlooked, already made up its mind. Whether anything else also enters at the second box of the diagram above is the whole of the argument between the dowsers and the sceptics. I hold the argument open. What I insist on is that the instrument be good enough to settle it: a weight that swings true, a chain that does not bind, and a board that holds the question fixed while the hand does its work.
IIA History in Hazel, Wire, and Silver
The pendulum is the younger child of an older instrument: the forked twig. In 1556 Georgius Agricola, town physician of the silver-mining city of Joachimsthal and the first great writer on mining, published De re metallica, and in its second book he described what the miners of the Erzgebirge did to find a vein. They cut a fork of hazel, held the two branches in their fists with the knuckles up, and walked; where the point dipped, they dug. Agricola had the scene engraved, and it is the first picture of dowsing that exists. He then, in the same chapter, told his reader that a serious miner should have nothing to do with it, and should rely instead on the natural signs of ore: the colour of the springs, the stunting of trees, the frost that melts early above a warm vein. He called it an enchanted twig. Martin Luther had already, in 1518, listed it among the breaches of the First Commandment.
None of this stopped it. When Elizabeth I brought German miners to Cornwall and the Lake District in the 1560s to teach the English to mine copper, the twig came with them, and within a century it was an English craft with English names: the dowsing rod, the wishing rod, the virgula divina. Then, in 1692, it left the mines. A wine merchant and his wife were murdered in a cellar in Lyon. A peasant from the Dauphiné named Jacques Aymar, who was known for finding water and thieves with his rod, was fetched; the rod dipped over the cellar, led him out of the city, down the Rhône by boat, into inns where it turned over the very beds the murderers had slept in, and finally into the prison at Beaucaire, where among fourteen prisoners it dipped over one: a hunchback, who confessed. The story went through France like fire. The Abbé de Vallemont wrote a book about it the next year, La Physique occulte, with plates showing the four ways to hold the rod; and Aymar was brought to Paris, where the Prince of Condé set him tests with buried metals and hidden guilty parties, all of which he failed. Both facts are true, and both are the whole history of dowsing in miniature: a performance in the field no one could explain, and a failure in the laboratory no one could excuse.
The swing of a weight replaced the dip of a twig around 1800. In Italy a dowser named Francesco Campetti was found who could apparently locate water and metal with a pendulum, and the Munich physicist Johann Wilhelm Ritter, discoverer of ultraviolet light, spent 1807 and 1808 testing him and publishing a journal, Der Siderismus, on the results. Ritter believed; his colleagues did not; but the pendulum had arrived as an instrument of inquiry, and it had one great advantage over the rod. A rod answers yes or no. A pendulum swings, circles, swings on a new axis, circles the other way, and stops: it has a vocabulary. The nineteenth century wrote a grammar for it, and the twentieth century built boards.
Chevreul explained it in 1833 and again in 1854. It did not matter. In France a generation of country priests took the pendulum up in earnest after the Great War: the Abbé Bouly, who coined the word radiesthésie for the whole practice, and the Abbé Mermet of Saint-Prex on Lake Geneva, whose book of 1935 on finding water, metals, lost objects, and disease at any distance made him the most famous dowser alive, consulted by the Vatican and by mining companies alike. Mermet designed a pendulum with a hollow chamber to hold a witness, a sample of the thing sought, and it is still the standard form. In 1913 the newspapers of Paris sent photographers to a public trial of water-finders in the country outside the city; in the pictures below every instrument of the craft is present at once: the whalebone rod, the wire rod, the watch-chain, the bob on a thread, and the little bottles of witness held in the left hand.
IIIWater, and the Percentage
Of all the things the pendulum and the rod have been asked to find, water is the one that can be checked, because a well is either wet or it is dry. It is therefore the one that has been tested, and the results deserve to be laid out plainly, since the makers of instruments ought to know what their instruments have and have not done.
The largest trial ever held was German, and government-funded. Between 1987 and 1988 the physicist Hans-Dieter Betz and his colleagues in Munich screened some five hundred dowsers and took the forty-three best into a barn, on whose ground floor a pipe carrying water could be moved from side to side without the dowser above knowing where. Each dowser walked the upper floor and marked where the pipe ran; there were, in the end, about ten thousand such trials. Betz reported that most dowsers did no better than guessing but that a few were reliably, and to him inexplicably, good. In 1995 the physiologist James Enright took the published data apart and showed that the best of the few, judged on all their trials rather than their best sessions, were no better than chance either. The Munich barn is, at present, the last word from the laboratory.
The field says something different, and the difference is the interesting part. Betz also ran a programme in the dry zone of Sri Lanka in which dowsers sited hundreds of wells in country where drilling is expensive and failure common; of 691 wells drilled where the dowsers pointed, 96 per cent found water, some at rates the hydrogeologists had not predicted. The United States Geological Survey, which has been asked about dowsing for a century and keeps a standing answer, points out the catch: in most inhabited country water lies within reach of a drill almost everywhere, so that a dowser’s ‘success rate’ is largely a measure of the aquifer under his feet, and the fair test is not whether the dowsed well is wet but whether it is wetter than one sited by a geologist, or at random. That test, wherever it has been run under control, the dowsers have not passed.
| Where and when | What was done | What was found |
|---|---|---|
| New Zealand, 1948 | P. A. Ongley tests 58 practising diviners on buried water and metal | None distinguishable from chance |
| United States, 1959 | Vogt & Hyman, Water Witching U.S.A. | ≈25,000 working dowsers; no test above chance |
| Munich barn, 1987–88 | Betz, Wagner & König; ≈500 candidates, 43 finalists, ≈10,000 trials over a movable pipe | Overall at chance; a handful claimed as ‘reliable’ |
| Same data, 1995 | J. T. Enright’s reanalysis of the Munich trials | The best performers no better than chance |
| Sri Lanka, 1990s | Betz’s field programme, 691 wells sited by dowsers | 96 % struck water |
| U.S. Geological Survey | Position statement | In most regions a well anywhere will find water; ‘success’ measures the aquifer, not the dowser |
And yet. Vogt and Hyman, who wrote the standard sceptical study of American water-witching in 1959, counted around twenty-five thousand practising dowsers in the United States, most of them farmers and well-drillers who witched their own ground and their neighbours’, and who, if you had shown them the Munich barn, would have shrugged and gone on doing it, because in their experience it worked. They were not stupid and they were not lying. What they knew, and could not say, was the shape of their own country: where the ground was green in August, where the alders stood, where the old wells had been. The rod let them consult that knowledge without having to own it. This is the pendulum’s real domain, and it is a large one: every question whose answer is already inside the asker, unheard.
IVWhat It Has Been Asked
Ore first, as already seen, and then water. Then everything. The uses of the pendulum through five centuries are a map of what people most wanted to know and could not find out any other way, and the map is worth walking.
The sex of a child. This is older than the pendulum and probably older than the rod: a wedding ring, or a needle, on a hair from the mother’s head, held over the belly. A circle for a girl, a line for a boy; or the reverse, depending on the village. It has been tried against the birth register, and it scores what a coin scores, which is to say half. But a woman who has asked it, and watched the ring go round, has been told something: what she expected. Midwives understood this perfectly well, and used the ring not to predict but to let the mother say aloud what she was hoping.
Lost things. The keys, the ring, the will, the body. Aymar’s murderers; the dowsers who were sent for when a child was missing. The pendulum over a map, which the radiesthesists called teleradiesthesia and which lets the whole question be asked from an armchair. Here the ideomotor account is at its strongest, since a person who has lost something usually knows more about where it is than they can say.
The body. Mermet and his followers held the pendulum over the patient, or over a drop of the patient’s blood, and read the organ and the ailment from the count and direction of the swing. French pharmacists of the 1930s sold pendulums beside the thermometers. The practice survives as medical radiesthesia and in a hundred kitchen tests of whether a food ‘agrees’; and it survives, in an entirely respectable form, as the pendulum used in some schools of chiropractic and kinesiology to read a muscle’s response. I make no medical claims and sell no medicine. I note that the instrument has been in the consulting room for ninety years.
War. In 1967 the newspapers reported that Marines of the First Division in Vietnam were walking ahead of patrols with two bent coat-hangers, looking for tunnels and buried mines, and that the practice had been quietly tolerated by their officers because the men believed in it and the alternative was nothing. Armies have always used what their soldiers believed in.
The self. The use that has grown while the others have faded, and the one for which the board was invented. A question written down; a pendulum held over a chart of answers; the hand allowed to move. Used as a decision tool, a meditation, a daily practice of asking what one actually wants and reading what the hand says back. For this use the quality of the instrument matters more, not less, because the answer is quiet and the noise of a bad pendulum, a kinked chain, a board that slides, drowns it.
VThe Types of Pendulum, and What Each Is For
Any weight on any thread is a pendulum, and the shapes that have survived are the ones that solved a problem. A weight needs to hang true, to start easily, to change its motion readily when the hand changes, and to stop cleanly when the hand stops; and it needs to do these things at a size that can be carried in a pocket and read across a table. These are engineering constraints, and the forms below are twelve answers to them, most of them found by people who never heard the word moment of inertia and none the worse for it.
Three quantities govern the feel of a pendulum. Its mass sets how much of the hand’s tremor it ignores: below about ten grams a pendulum is nervous, above about thirty it is stubborn, and the sweet range for most hands is fourteen to twenty-four. The height of its centre of mass above the point sets how it damps: a low, pointed bob settles in three beats and reads sharply; a high, round one keeps swinging and reads softly. And the chain length sets its period, which should match the natural rhythm of the hand that holds it: fifteen to twenty-five centimetres for nearly everyone, and the length to find by trial rather than by rule.
Conical, or plumb-bob
The mason’s weight, and still the best all-round form. Mass low, point sharp, the swing damped quickly by the shoulder of the cone. Settles in three or four beats. Mine are turned from solid sterling or from brass, 14–22 g.
Teardrop
A cone smoothed into a drop. Slightly more mass held high, so it swings a little longer and reads a little softer. The classic shape for faceted crystal.
Sphere
The same from every side, and therefore without any preferred axis: it will as readily circle as swing. Favoured by those who read rotation. Heavier for its size than a cone of the same diameter.
Mermet (chambered)
The Abbé Mermet’s design: a cylinder that unscrews to hold a witness, a grain of the thing sought, above a conical point. The witness is the theory; the low, heavy point is the physics. A superb pendulum whether or not the chamber is used.
Isis
Egyptian-revival form of the 1930s: a stack of diminishing disks on a spindle above the point. The disks were called batteries by the radiesthesists; mechanically they raise the centre of mass and lengthen the period.
Karnak
A ribbed cylinder-and-cone. The rings add nothing to the swing but a great deal to the grip of the eye, and the form is handsome in silver.
Osiris
Four graduated spheres on a stem. Its centre of mass sits well up the stem, so it is slow, deliberate, and hard to hurry: a pendulum for long questions.
Helical, or spiral
A coiled spring of silver or bronze wire ending in a point. This is the odd one, and the interesting one: a spring pendulum is two oscillators in one, and at the right chain length the bounce and the swing trade energy back and forth by themselves. It feels alive in the hand because, in a strict mechanical sense, it is doing something no plain bob can do.
Merkaba
Two interpenetrating tetrahedra, the star tetrahedron of the geometers, cut in crystal or cast in silver. Eight points, and no obvious ‘down’ until it is hung; it finds its own axis.
Crystal point
A natural six-sided prism of quartz, terminated, capped in silver. Light for its size (quartz is 2.65 g/cm³, a quarter the density of silver), so it answers quickly to small hands and small questions.
The ring on a thread
Chevreul’s instrument, and the midwife’s: a wedding ring, a hair or a silk thread. No pendulum is simpler, and every result ever obtained with a pendulum was first obtained with this.
The pierced coin
The Chinese cash pendulum, a brass coin on a red cord. Flat, so it planes on the air and swings in a wide slow arc; the square hole was said to be the earth inside the circle of heaven.
On the helical, or spiral, pendulum a further word is owed, because it is the one type whose behaviour is genuinely different rather than merely differently shaped. A weight on a spring is two oscillators: it swings, as any pendulum does, and it bounces, as any spring does. When the spring is chosen so that its bounce is close to twice the frequency of the swing, the two motions couple, and the pendulum, set bouncing, will of its own accord begin to swing, then stop swinging and bounce again, exchanging its energy between the two in a slow cycle that nobody has to drive. Physicists call it the swinging spring, and use it to teach nonlinear resonance. Dowsers call it lively. Both are right, and it is why a well-made helix in the hand seems to have opinions of its own.
VIThe Stones
A crystal pendulum is a compromise, and a good one. Stone is light, which makes the pendulum quick; stone is beautiful, which makes it loved and therefore used; and each stone brings with it two or three thousand years of association that the holder cannot help but bring to the question. The compromise is in the weight: quartz is a quarter the density of silver, so a crystal point the size of a silver cone weighs a quarter as much, and either needs to be larger or accepts being nervous. I cap mine in silver to bring the mass up and the centre of gravity down, and I cut none of them: a natural termination, unbroken, is worth more than any polish.
Quartz, clear, is the universal stone, and the only one with a modern physics of its own worth mentioning: it is piezoelectric, which the Curie brothers found in 1880, and it keeps the time in every watch in the world. Amplification and clarity in the lore; in the hand, a cool weight that shows the chain through it. Amethyst is quartz coloured by iron and irradiation, the stone of sobriety and of the third eye, and the one most often chosen for a first pendulum. Smoky quartz and citrine are the same mineral again, grounding and warming respectively. Rose quartz, for the heart; it does not form points, so it is cut, and I set it as a sphere.
Black tourmaline is the protective stone, and, like quartz, it has a physics: it is pyroelectric, gaining a charge when warmed, which is why Dutch traders in the eighteenth century called it the ash-puller, having watched it draw ash out of their pipes. Obsidian, volcanic glass, the Aztec mirror-stone, light and very sharp when it breaks, a stone for looking at what one would rather not. Lapis lazuli for truth and insight; labradorite, which flashes blue and gold from a grey ground, for intuition and the unseen; hematite, iron oxide, twice the density of quartz and the stone of blood and grounding, when a heavy stone pendulum is wanted; selenite, which I am asked for and refuse as a bob, since it is soft enough to scratch with a fingernail and will not survive a year of use.
| Material | Density g/cm³ |
|---|---|
| Gold | 19.3 |
| Silver | 10.49 |
| Bronze | 8.8 |
| Brass | 8.5 |
| Iron | 7.87 |
| Hematite | 5.26 |
| Malachite | 3.6–4.0 |
| Black tourmaline | 3.0–3.2 |
| Lapis lazuli | 2.7–2.9 |
| Labradorite | 2.70 |
| Quartz, amethyst, citrine | 2.65 |
| Obsidian | 2.40 |
| Selenite | 2.30 |
Density is what a pendulum-maker actually chooses when they choose a material: for a given shape it sets the weight, and weight sets the steadiness.
VIIThe Case for Silver
I make pendulums in brass and bronze because they are honest metals and some people want them. I make them in silver because it is the right metal, and the reasons are of two kinds, which for once agree.
The physical reasons first. Silver is the most electrically and thermally conductive metal there is, ahead of copper and well ahead of gold: an electron moves through it with less resistance than through anything else that can be hung on a chain. It is the most reflective: a polished silver surface returns about ninety-five per cent of the light that falls on it, which is why the first mirrors that were not simply polished metal were glass silvered on the back. It is dense, ten and a half grams to the cubic centimetre, so that a cone the size of a fingertip weighs twenty grams and swings with a steadiness no stone of that size can match. It is soft enough to take a fine turned edge and a hallmark, hard enough, as sterling, to keep them. And it is solid: a silver pendulum is silver all the way through, so there is no plating to wear away at the point where the thumb rubs it, and a hundred years from now it will be exactly what it is today, worth its weight and answering to a polish.
Tarnish is part of the case, not against it. Silver darkens because it takes sulphur out of the air, slowly, and writes the record of every room it has been in onto its skin; a pendulum used daily wears bright where it is touched and dark where it is not, and comes to look like the hand that uses it. A minute with a cloth and it is new. Gold does not do this, and that is the argument for gold; the argument for silver is that it lives.
The older reasons are the same reasons in an older language. Silver is the metal of the Moon, Luna to the alchemists, as gold is the Sun’s, and the Moon governs the tides, the night, the reflective and receptive side of the mind: exactly the faculty the pendulum is meant to consult. It is the mirror-metal, and the pendulum is a mirror. It is the metal of purification in nearly every tradition that has had it, from the silver vessels of the Temple to the silver bullet, and its actual antibacterial action, which hospitals now use in dressings, was known to the Phoenicians, who stored water in silver jars. It is held to be the conductor of psychic sensitivity, the metal that neither adds to nor takes from the current passing through it, and whatever one makes of that as a claim, it is, as a description of silver’s conductivity, simply correct. When the tradition says that a silver pendulum on a silver chain is one unbroken circuit from the fingers to the point, the metallurgist has no objection.
So my chains are solid sterling too, every link soldered shut, with no clasp at the bob, since a clasp is a hinge and a hinge is play, and play in the chain is noise in the answer. The finger-bead at the top is silver or stone. The whole is hallmarked, and weighs what it is worth. A plated pendulum is a pendulum that will one day be brass; a silver one is a pendulum that will one day be your grandchild’s.
VIIIThe Boards: Veneer, Stone, and Geometry
A pendulum without a board is a witness without a court. It moves, and the holder decides what the movement meant, after the fact, with all the freedom of interpretation that implies. A board takes that freedom away. It fixes the frame before the question is asked: this axis is yes, that one no, this arc runs from nought to a hundred, these are the letters. The hand then has only to move, and the board does the reading. It is the difference between a needle and a needle on a dial, and it is why a good board makes a pendulum honest.
I make mine the way instrument cases and the cabinets of the best marquetry were made: a stable core, veneered on both faces so it cannot cup, the chart inlaid rather than printed, so that it is part of the wood and will not wear, the whole finished under enough coats that the surface reads as glass and the pendulum’s shadow is visible on it. The veneers are sawn, not sliced, where I can get them, which is thicker and truer in colour, and every species I use is legally traded; I do not use Brazilian rosewood or any wood on the appendices. The letters and lines are holly, the whitest wood in the world, and silver wire let into a groove and planed flush.
The veneers
Bubinga
West Africa. A deep red-brown with a fine, waving figure; takes a glass polish. My default ground for a dark board.
Wenge
Central Africa. Nearly black, with a coarse straight grain that reads as fine parallel lines: a natural ruled field for a chart.
Zebrawood
Gabon and Cameroon. Cream and dark brown in bold stripes. Cut on the quarter it gives the rays of a fan chart for nothing.
Purpleheart
South America. Brown when cut, violet within a week of daylight, and darkening to plum with the years.
Padauk
Africa and Andaman. Vermilion, mellowing to a deep coral. The colour most often asked for in a heart chart.
Macassar ebony
Sulawesi. Black streaked with tan. Dense enough to carry a fine engraved line without tearing; the darkest wood I use.
Hawaiian koa
Curly koa has a chatoyance, a shimmer that moves as the board is tilted, that no photograph carries.
Bird’s-eye maple
North America. A pale ground full of tiny swirling eyes, the cause of which is still argued over by foresters.
Figured walnut
Claro and English walnut crotch and burl. The classic ground for a silver inlay: warm, and quiet.
Quilted maple
Pacific Northwest. A billowing, three-dimensional figure; under a pendulum it seems to be moving too.
Holly
The whitest wood there is. Used for stringing, for the fine lines of a chart, and for the letters of an alphabet board.
The minerals
Stone in a board does two things. It marks the pivot, the point over which the pendulum hangs and from which every reading is taken, with something that draws the eye and holds it; and it brings to the board whatever the holder believes about the stone, which is not nothing. I set solid stone in silver bezels, as jewellers do, and crushed stone bound in resin into engraved lines and arcs, as the inlayers of the Southwest do, and I sand both flush and finish over them.
Lapis lazuli
Afghan lazurite with pyrite. The stone of the Egyptian and Sumerian sky, ground for ultramarine. Set as a solid disk at the pivot of the board, or as crushed inlay in an engraved line. Associated with insight, truth, and the third eye.
Malachite
Banded copper carbonate from the Congo. Its concentric rings, cut through, become a natural target. Traditionally a stone of transformation and protection; practically, a stone that must be sealed, since it is soft and its dust is copper.
Turquoise
Sleeping Beauty and Kingman turquoise, with its brown or black matrix. The stone of sky and water in the American Southwest and Persia. I set it in silver bezels, as the smiths of the Southwest do, rather than gluing it down.
Mother of pearl and abalone
The inside of the shell: nacre, aragonite platelets laid in brick-courses that split light into its colours. The pendulum swings above it and the surface changes as the eye moves. Lunar, protective, and very old as an inlay: the Sumerians used it on the Standard of Ur.
Tiger’s eye
Quartz that has replaced crocidolite fibres, keeping their silk. A chatoyant band of gold that follows the light. Grounding and courage in the lore; a perfect material for the pivot of a percentage chart.
The geometry
Every chart is a geometry, and most are bad ones: a semicircle stamped on a card, its centre nowhere in particular, its divisions where the printer’s software put them. I lay mine out with a compass, from the figures that were laid out with a compass before there was anything else to lay them out with, and I do it for two reasons. The first is that the eye reads proportion whether or not the mind does: a board built on the vesica or the golden section is one the hand settles over, without being told why. The second is that these figures were, for the people who cut them into temple walls, the shape of the question itself: how the one becomes the many, how the circle contains the line. A pendulum board is a small machine for asking that, and it seems right that it should be drawn the same way.
Vesica piscis
Two circles, each through the other’s centre. The lens between them is √3 high for every 1 wide. The arc of every board I make is struck from this figure.
Seed of Life
Seven circles: the first six steps of the compass around a centre. The oldest ornament in the world, cut into the temple at Abydos.
Flower of Life
Nineteen circles in two rings, bounded by a double circle. Leonardo drew pages of it. Its lattice is what a pendulum board wants: an even field with a centre.
Metatron’s Cube
Thirteen circles from the Flower, every centre joined to every other: 78 lines, containing in projection all five Platonic solids.
The golden rectangle
1 : 1.618. My boards are cut to it, and the pivot sits where the spiral converges, a little below and to one side of the centre, where the eye rests.
IXMethod
Sit. Rest the elbow of the holding arm on the table, or do not, but decide, and do the same every time. Hold the chain between thumb and forefinger at the bead, the pendulum a finger’s width above the pivot of the board. Still it with the other hand. Then ask the board to show you yes, and wait, and do nothing. It will move. Note the axis. Still it, ask for no, and note that. This is the calibration, and it is different for every hand and some days for the same hand; it takes a minute and it is not to be skipped.
Ask one thing at a time, in words that have one answer, and ask it aloud or write it down; a question that is only half-thought gets a half-answer. Do not look for the answer you want while the pendulum is moving; look at the pivot, and let the board read the swing. When it has settled, write the answer next to the question, with the date. A book of questions and answers kept for a year is the only instrument that will ever tell you whether your pendulum is worth listening to, and it is the one no one sells.
Clean the pendulum. Polish the silver. Keep the board flat and out of the sun, since purpleheart and padauk will change colour and every wood will move. Do not lend it. Not because another hand will spoil it, but because the calibration is yours, and the answers are.