| 1 |
C7-11 COLLISIONS OF BALLS - EQUAL MASSES |
| 1 |
C7-25 SUPERBALL, VACUUM MUD AND WOOD BLOCK COLLISIONS |
| 1 |
C8-04 HILL TRACK |
| 13 |
F1-01 FLUID PRESSURE VS. DEPTH |
| 6 |
F1-02 FLUID PRESSURE VS. DEPTH - ANEROID GAUGE |
| 4 |
F1-03 PASCAL'S VASES |
| 9 |
F1-04 EQUILIBRIUM TUBES |
| 4 |
F1-05 DOES WATER SEEK ITS OWN LEVEL |
| 9 |
F1-06 WATER SEEKS ITS OWN LEVEL |
| 9 |
F1-11 HYDRAULIC PRESS |
| 8 |
F1-12 PASCAL'S LAW - COILED TUBE PARADOX |
| 5 |
F1-21 LIPLESS STRAW |
| 19 |
F2-01 ARCHIMEDES' PRINCIPLE |
| 2 |
F2-03 CARTESIAN DIVER - EXPLICIT VERSION |
| 8 |
F2-04 BUOYANCY - SPHERE AND WATER |
| 16 |
F2-05 BUOYANCY - BOAT AND ROCK |
| 5 |
F2-07 BUOYANCY - PEPSI AND DIET PEPSI |
| 2 |
F2-08 BUOYANCY - BATTLESHIP IN BATHTUB |
| 7 |
F2-11 HYDROMETER |
| 7 |
F2-12 HOT AIR BALLOON |
| 8 |
F2-21 REACTION TO BUOYANT FORCE |
| 6 |
F2-22 BUOYANCY PARADOX - ACCELERATED FRAME |
| 11 |
F2-23 BUOYANCY PARADOX- INVERTED BLOCK |
| 4 |
F2-24 ACCELERATED BUOYANT BALL |
| 3 |
F2-25 BALANCE PARADOX - BUOYANCY WITH CROSSOVER |
| 1 |
F2-31 BUOYANT BALLS IN BEANS |
| 2 |
F2-32 FLOATING SQUARE BAR |
| 2 |
F3-01 SURFACE TENSION - JOLLY BALANCE |
| 2 |
F3-02 SURFACE TENSION - BALLOONS |
| 2 |
F3-04 SURFACE TENSION - THREAD ON WATER |
| 3 |
F3-11 SURFACE TENSION - CAPILLARY TUBES |
| 2 |
F4-02 VISCOSITY OF AIR |
| 2 |
F4-11 LAMINAR AND TURBULENT FLOW OF AIR |
| 1 |
F4-14 WIND TUNNEL |
| 2 |
F4-24 HILSCH VORTEX TUBE |
| 5 |
F4-61 HERO'S FOUNTAIN |
| 10 |
F4-63 MARRIOTTE'S BOTTLE |
| 5 |
F5-01 BERNOULLI'S PRINCIPLE - TOY CAR AND BALL |
| 7 |
F5-03 BERNOULLI'S PRINCIPLE - THIN METAL SHEETS |
| 1 |
F5-04 BERNOULLI'S PRINCIPLE - LARGE BALL AND FUNNEL |
| 3 |
F5-05 BERNOULLI'S PRINCIPLE - SMALL BALL AND FUNNEL |
| 7 |
F5-06 BERNOULLI'S PRINCIPLE - BEACH BALL |
| 6 |
F5-07 BERNOULLI'S PRINCIPLE - SPOOL AND CARDBOARD |
| 7 |
F5-09 BERNOULLI'S PRINCIPLE - HAIRDRYER AND PING PONG BALL |
| 4 |
F5-10 CHIMNEY DRAW WITH WATER |
| 5 |
F5-11 AIRPLANE WING |
| 14 |
F5-21 VENTURI TUBE WITH MANOMETERS |
| 3 |
F5-22 VENTURI TUBE WITH PING PONG BALLS |
| 4 |
F5-23 VENTURI TUBE WITH WATER |
| 1 |
F5-24 VENTURI TUBE WITH WATER - MANOMETERS |
| 6 |
F5-31 MAGNUS EFFECT - FLETTNER'S SHIP |
| 2 |
F5-32 CURVE BALL |
| 32 |
G1-01 EXAMPLES OF SIMPLE HARMONIC MOTION |
| 14 |
G1-11 COMPARISON OF SHM AND UCM |
| 18 |
G1-12 PENDULUM AND ROTATING BALL |
| 2 |
G1-13 MASS ON STRING |
| 21 |
G1-14 PENDULA WITH DIFFERENT MASSES |
| 14 |
G1-15 PENDULA WITH 4 TO 1 LENGTH RATIO |
| 3 |
G1-17 PENDULUM WITH LARGE-ANGLE OSCILLATION - PORTABLE |
| 3 |
G1-18 PENDULUM WITH FORCE SCALE |
| 13 |
G1-31 HOOKE'S LAW AND SHM |
| 4 |
G1-32 MASS ON SPRING - WITH STAND |
| 6 |
G1-33 MASSES AND SPRINGS WITH SPIDER |
| 5 |
G1-34 AIR TRACK - SIMPLE HARMONIC MOTION |
| 3 |
G1-35 MASS ON SPRING - EFFICIENT MODEL |
| 2 |
G1-41 TORSIONAL PENDULUM |
| 7 |
G1-42 LARGE TORSIONAL PENDULUM |
| 9 |
G1-42 TORSIONAL PENDULUM - LARGE |
| 8 |
G1-51 INVERTED SPRING PENDULUM |
| 15 |
G1-52 STRINGLESS PENDULUM |
| 14 |
G1-53 SHM - CAN IN WATER TANK |
| 2 |
G1-54 MASS'S DOUBLE PENDULUM |
| 2 |
G1-59 BIFILAR PENDULUM |
| 6 |
G1-60 CHAOS - TWO BIFILAR PENDULA |
| 4 |
G1-71 LISSAJOUS FIGURES - SAND PENDULUM |
| 8 |
G1-82 PENDULUM WAVES |
| 6 |
G2-01 MASS ON SPRING - HAND HELD |
| 21 |
G2-02 FORCED HARMONIC MOTION WITH DAMPING - LARGE |
| 10 |
G2-03 RESONANCE IN TORSIONAL PENDULUM - PROJECTION |
| 6 |
G2-04 DAMPED OSCILLATIONS |
| 1 |
G2-05 AIR TRACK - DRIVEN AND DAMPED OSCILLATIONS |
| 4 |
G2-07 PSYCHOACOUSTIC VIBRATION TRANSDUCER |
| 2 |
G2-11 RESONANT SAW BLADES - HAND DRIVEN |
| 6 |
G2-21 COUPLED PENDULA |
| 1 |
G2-28 PENDULA WITH VARIABLE DRIVER |
| 23 |
G3-01 SHIVE WAVE MACHINE - TRAVELING WAVES |
| 10 |
G3-02 SHIVE WAVE MACHINE - SUPERPOSITION OF PULSES |
| 10 |
G3-03 SHIVE WAVE MACHINE - REFLECTION OF PULSES |
| 13 |
G3-04 SHIVE WAVE MACHINE - STANDING WAVES |
| 4 |
G3-05 SHIVE WAVE MACHINE - PARTIAL REFLECTIONS |
| 6 |
G3-21 TRANSVERSE WAVES ON A LONG SPRING |
| 7 |
G3-22 VELOCITY OF TRANSVERSE WAVE ALONG ROPE |
| 6 |
G3-23 TRANSVERSE WAVES ON A LONG SPRING - FREE END |
| 3 |
G3-24 SLINKY ON LECTURE TABLE - TRAVELING WAVES |
| 1 |
G3-26 AIR TRACK - LONGITUDINAL WAVES |
| 34 |
G3-28 SUSPENDED SLINKY |
| 5 |
G3-41 WAVE MODELS - PROJECTION |
| 7 |
G3-43 WHIP |
| 8 |
G3-44 WAVE-DRIVEN BUMPER JACK |
| 3 |
G3-45 RESONANCE OF WIRES |
| 3 |
G3-46 STANDING WAVES IN A WIRE LOOP |
| 23 |
G3-51 ROPE WAVE GENERATOR - FREQUENCY VS. |
| 24 |
G3-52 ROPE WAVE GENERATOR - ROPE TENSION VS. |
| 2 |
G3-53 STANDING WAVES IN A STRING |
| 1 |
G4-01 RIPPLE TANK - PORTABLE |
| 3 |
G4-02 RIPPLE TANK |
| 2 |
G4-03 RIPPLE TANK - DOPPLER EFFECT |
| 2 |
G4-12 STANDING WAVES ON A SOAP FILM |
| 3 |
G4-22 CHLADNI FIGURES - OSCILLATOR DRIVEN |
| 2 |
G4-41 SOLITONS |
| 12 |
H1-01 BELL IN VACUUM |
| 6 |
H1-02 SPEAKER AND CANDLE |
| 2 |
H1-03 BELLS |
| 4 |
H1-11 MICROPHONE AND OSCILLOSCOPE |
| 4 |
H1-13 WAVEFORM GENERATOR, SPEAKER AND OSCILLOSCOPE |
| 2 |
H1-21 SPEED OF SOUND - PHASE CHANGE |
| 9 |
H1-23 SPEED OF SOUND IN ALUMINUM |
| 1 |
H1-24 SPEED OF SOUND IN HELIUM |
| 5 |
H1-31 SOUND LEVEL METER |
| 2 |
H1-32 WAVETEK AND AUDIO CART - EQUAL SOUND LEVEL STEPS |
| 2 |
H1-41 ULTRASONIC MOTION DETECTOR |
| 1 |
H2-02 PARABOLIC MICROPHONE |
| 1 |
H2-11 SOUND LENS |
| 17 |
H2-21 AUDIBLE YOUNG'S EXPERIMENT - GROUP LISTENING |
| 2 |
H2-22 INTERFERENCE - TRANSPARENCIES |
| 2 |
H2-25 QUINCKE'S INTERFERENCE TUBES |
| 4 |
H2-26 PHASE REVERSAL BETWEEN STEREO SPEAKERS |
| 4 |
H2-28 FOURIER SYNTHESIZER - ADDITION OF WAVES |
| 8 |
H2-32 SPEAKER WITH BAFFLE |
| 22 |
H2-41 DOPPLER BALL |
| 2 |
H2-42 DOPPLER EFFECT - TUNING FORK ON STRING |
| 10 |
H2-51 BEATS - AUDIO OSCILLATORS, SPEAKERS & OSCILLOSCOPE |
| 20 |
H2-52 BEATS AND RESONANCE - TUNING BARS |
| 2 |
H2-53 BEATS - AUDIO OSCILLATORS AND SPEAKERS |
| 1 |
H2-54 BEATS - MOIRE PATTERN |
| 3 |
H3-01 STANDING SOUND WAVES - TWO SOURCES |
| 5 |
H3-02 STANDING SOUND WAVES - REFLECTION |
| 3 |
H3-05 KUNDT'S TUBE - OSCILLATOR DRIVEN |
| 4 |
H3-11 TUNING FORKS AND RESONANT TUBE |
| 3 |
H3-14 TWIRL-A-TUNE |
| 4 |
H3-17 FLAME TUBE |
| 2 |
H3-21 SOUND RESONANCE IN WATER TUBE |
| 2 |
H3-22 RESONANCE TUBE - OSCILLATOR AND PLUNGER |
| 3 |
H3-23 RESONANCE TUBE - OSCILLATOR, PLUNGER & MICROPHONE |
| 12 |
H3-24 OPEN AND CLOSED PIPES |
| 22 |
H3-61 BEAKER BREAKER |
| 7 |
H3-71 STROKED ALUMINUM ROD |
| 1 |
H3-72 TUNING RODS |
| 11 |
H4-01 FOURIER SYNTHESIS |
| 3 |
H4-02 FOURIER ANALYSIS - WAVE SHAPE AND SPECTRUM |
| 1 |
H4-04 FOURIER ANALYSIS |
| 3 |
H4-33 ORGAN PIPE |
| 2 |
H4-51 MODULATION - AM AND FM |
| 1 |
H5-21 THREE DECIBELS |
| 5 |
H6-04 HELIUM VOICE |
| 3 |
H6-05 SULFUR HEXAFLUORIDE VOICE |
| 8 |
I1-01 THERMOMETERS |
| 21 |
I1-11 THERMAL EXPANSION - BALL AND HOLE |
| 18 |
I1-13 THERMAL EXPANSION - BIMETAL STRIP |
| 2 |
I1-14 THERMAL EXPANSION OF ALUMINUM - OPTICAL LEVER |
| 6 |
I1-15 THERMAL EXPANSION - PIN BREAKER |
| 2 |
I1-17 THERMOSTAT - MODEL |
| 2 |
I1-21 WATER NEAR 4 DEGREES CELCIUS |
| 1 |
I1-22 WATER DENSITY VS TEMPERATURE |
| 5 |
I1-32 RUBBER BAND CONTRACTION DURING HEATING |
| 3 |
I1-41 THERMOELECTRIC MAGNET |
| 1 |
I2-01 CROOKES' RADIOMETER |
| 2 |
I2-03 CROOKES' RADIOMETER - ROTATION REVERSAL |
| 2 |
I2-04 WIEN'S LAW OF THERMAL RADIATION |
| 3 |
I2-08 RADIATIVE HEAT TRANSFER |
| 1 |
I2-10 DEWARS - SILVERED AND UNSILVERED |
| 19 |
I2-21 THERMAL CONDUCTIVITY IN METALS |
| 4 |
I2-22 THERMODYNAMICS BY TOUCH |
| 1 |
I2-24 THERMAL CONDUCTIVITY IN WATER |
| 4 |
I2-25 THERMAL CONDUCTIVITY IN BUILDING MATERIALS |
| 3 |
I2-41 CONVECTION - POWDER IN WATER |
| 2 |
I2-43 CONVECTION - HOT PLATE |
| 4 |
I2-44 CONVECTION - CANDLE IN CYLINDER |
| 2 |
I3-04 GALILEAN THERMOMETER |
| 2 |
I3-15 MAGDEBURG HEMISPHERES - PORTABLE |
| 7 |
I3-31 IDEAL GAS LAW - VOLUME OF ONE MOLE |
| 1 |
I3-32 ISOBARIC EXPANSION OF AIR |
| 2 |
I3-33 HELIUM BALLOON ON LIQUID NITROGEN |
| 6 |
I3-41 BOYLE'S LAW - PROJECTION |
| 1 |
I3-42 BOYLED MARSHMALLOWS |
| 2 |
I3-43 TIRE PRESSURE - UNLOADED AND LOADED |
| 5 |
I3-51 CHARLES' LAW - PROJECTION |
| 18 |
I3-52 CONSTANT VOLUME GAS THERMOMETER - ABSOLUTE |
| 5 |
I4-01 PVT PHASE DIAGRAMS FOR CO2 AND H2O |
| 4 |
I4-03 LATENT HEAT - ICE TO WATER TO STEAM |
| 2 |
I4-12 BOILING WATER BY PUMPING |
| 6 |
I4-17 AIR BALLOON ON LIQUID NITROGEN |
| 10 |
I4-31 ICE BOMB |
| 2 |
I4-32 FREEZING WATER BY PUMPING |
| 1 |
I4-34 HAND WARMER |
| 1 |
I4-51 SUBLIMATION OF DRY ICE - PROJECTION |
| 17 |
I5-01 MECHANICAL EQUIVALENT OF HEAT - SHOT BAG |
| 9 |
I5-03 MECHANICAL EQUIVALENT OF HEAT - JOULE'S METHOD |
| 5 |
I5-11 ADIABATIC PROCESS - AIR PISTON WITH THERMISTOR |
| 16 |
I5-12 ADIABATIC EXPANSION OF AIR - FOG IN BOTTLE |
| 8 |
I5-13 ADIABATIC EXPANSION OF AIR - GRAPH OF TEMP |
| 3 |
I5-14 LIQUEFICATION OF NITROGEN |
| 5 |
I5-15 ADIABATIC EXPANSION OF AIR - CARBON DIOXIDE |
| 3 |
I5-22 FIRE SYRINGE |
| 6 |
I5-31 STEAM ENGINE - STATIONARY |
| 3 |
I5-32 STIRLING ENGINE |
| 3 |
I5-33 STEAM ROLLER |
| 6 |
I5-34 STIRLING ENGINE - VISIBLE |
| 6 |
I5-41 ENDOTHERMIC REACTION - ENTROPY |
| 17 |
I5-51 SPECIFIC HEAT - ALUMINUM AND COPPER |
| 9 |
I6-01 GAS PRESSURE - MODEL |
| 7 |
I6-03 EQUIPARTITION OF ENERGY |
| 5 |
I6-11 BROWNIAN MOTION WITH TV |
| 6 |
I6-21 GAS DIFFUSION - MODEL |
| 1 |
I6-24 DIFFUSION VELOCITY |
| 2 |
I6-31 MOLECULAR MOTION DEMO - BROWNIAN MOTION |
| 1 |
I6-32 MOLECULAR MOTION DEMO - RANDOM MOTION IN GASES |
| 4 |
I6-33 MOLECULAR MOTION DEMO - GAS PRESSURE |
| 4 |
I6-34 MOLECULAR MOTION DEMO - TEMPERATURE OF A GAS |
| 1 |
I6-37 MOLECULAR MOTION DEMO - VAN DER WAALS FORCES |
| 1 |
I6-39 MOLECULAR MOTION DEMO - CHARLES' LAW |
| 1 |
I6-40 MOLECULAR MOTION DEMO - SOLIDS AND LIQUIDS |
| 1 |
I6-41 MOLECULAR MOTION DEMO - MEAN FREE PATH |
| 4 |
I6-51 ENTROPY - SORTING MARBLES |
| 1 |
I6-52 ENTROPY - FOUR BALLS IN GAS DIFFUSION MODEL |
| 22 |
J1-01 TRIBOELECTRICITY - CHARGING BY FRICTION |
| 3 |
J1-02 TRIBOELECTRICITY - WATER JET IN AIR |
| 4 |
J1-03 KILOVOLT CARPET |
| 4 |
J1-04 KILOVOLT INSTRUCTOR |
| 8 |
J1-05 CHARGED BALLOONS |
| 11 |
J1-11 ELECTROPHORUS |
| 18 |
J1-12 INDUCTION - ELECTROSCOPE |
| 11 |
J1-13 ELECTROSTATIC INDUCTION |
| 18 |
J1-21 ELECTROSTATIC ATTRAC AND REPULS - CHARGED CYLINDERS |
| 8 |
J1-24 ELECTROSTATIC HAIR RAISING |
| 2 |
J1-25 VAN DE GRAAFF - TRAINED RABBIT |
| 7 |
J1-26 VAN DE GRAAFF - REPULSION OF PIE PANS |
| 4 |
J1-27 QUALITATIVE EXISTENCE OF ELECTROSTATIC FORCES |
| 3 |
J1-28 COULOMBS LAW - PROJECTION |
| 4 |
J1-29 VAN DE GRAAFF - PENDULUM |
| 19 |
J1-41 CONDUCTORS AND INSULATORS |
| 10 |
J2-03 VAN DE GRAAFF GENERATOR WITH GROUND SPHERE |
| 1 |
J2-13 PLASMA MACHINE - EYE OF THE STORM |
| 8 |
J2-14 LIGHTNING ROD SIMULATOR |
| 1 |
J2-15 ELECTROSTATIC SMOKE PRECIPITATOR |
| 1 |
J2-17 ELECTRIC WIND |
| 2 |
J2-31 JACOB'S LADDER |
| 4 |
J2-51 ELECTROSTATIC MOTOR |
| 13 |
J3-01 EXISTENCE OF ELECTRIC FIELDS |
| 5 |
J3-02 ELECTRIC FIELD OF RING OF CHARGE - MODEL |
| 13 |
J3-03 ELECTRIC FIELD LINES |
| 3 |
J3-04 ELECTRIC FIELD LINES - SOAP BUBBLES |
| 6 |
J3-05 VAN DE GRAAFF - INDUCTION WITH SPHERES AND NEON BULBS |
| 8 |
J3-06 ELLIPSOIDAL CONDUCTOR |
| 9 |
J3-07 VAN DE GRAAFF - DISCHARGE TO VARIOUS RADII |
| 6 |
J3-08 VAN DE GRAAFFS - INTERACTING FIELDS |
| 6 |
J3-11 EQUIPOTENTIALS/LINES OF FORCE - ONE CHARGE |
| 6 |
J3-12 EQUIPOTENTIALS/LINES OF FORCE - TWO POSITIVE CHARGES |
| 3 |
J3-13 POTENTIAL SURFACE MODEL WITH E FIELD VECTORS |
| 6 |
J3-14 FLUX MODEL - ELECTROSTATICS |
| 8 |
J3-21 FARADAY CAGE |
| 13 |
J3-22 FARADAY CAGE - ELECTROSCOPE |
| 8 |
J3-23 FARADAY CAGE - RADIOWAVES |
| 14 |
J3-24 HOLLOW CONDUCTING SPHERE |
| 16 |
J4-01 PARALLEL PLATE CAPACITOR |
| 3 |
J4-02 PARALLEL PLATE CAPACITOR - SYMMETRIC |
| 6 |
J4-03 PARALLEL PLATE CAPACITOR - SERIES CAPACITORS |
| 3 |
J4-03 PARALLEL PLATE CAPACITOR - SERIES CAPCITORS |
| 7 |
J4-04 PARALLEL PLATE CAPACITOR - IONIZATION OF AIR |
| 9 |
J4-11 POLAR AND NONPOLAR LIQUIDS |
| 1 |
J4-12 ELECTROSTATIC FORCE - MOVING LUMBER |
| 21 |
J4-22 PARALLEL PLATE CAPACITOR WITH DIELECTRIC |
| 6 |
J4-23 POLARIZATION OF DIELECTRIC - DISSECTIBLE LEYDEN JAR |
| 19 |
J4-31 ENERGY STORED IN A CAPACITOR |
| 17 |
J4-32 DISCHARGE OF CAPACITOR WITH BANG |
| 12 |
J4-41 CAPACITORS |
| 10 |
J4-42 CAPACITORS IN SERIES AND PARALLEL |
| 3 |
J4-43 CAPACITORS IN SERIES AND PARALLEL WITH PROJECTION METER |
| 2 |
J4-51 THEREMIN |
| 2 |
K1-01 FORCE BETWEEN CURRENT-CARRYING WIRES |
| 2 |
K1-03 FORCE ON CURRENT IN MAGNETIC FIELD |
| 1 |
K1-15 OSCILLOSCOPE CRT - DEFLECTION BY ELECTRIC FIELD |
| 2 |
K1-21 TORQUE ON CURRENT LOOP IN MAGNETIC FIELD |
| 2 |
K3-01 INDUCTION IN A TRANSFORMER |
| 2 |
K4-01 AC/DC GENERATOR |
| 2 |
K4-22 DC MOTOR |
| 2 |
K4-41 MOTOR-GENERATOR PAIR |
| 1 |
K5-11 BATTERY MODEL |
| 3 |
K5-12 BATTERY AND CURRENT - WORKING MODEL |
| 8 |
K5-13 ELECTRIC CURRENT - MODEL |
| 1 |
K5-14 ELECTRIC CELL |
| 17 |
K5-31 OHM'S LAW |
| 10 |
K5-32 RESISTANCE VS DIAMETER AND LENGTH |
| 3 |
K5-33 CONDUCTIVITY OF SALT SOLUTION |
| 3 |
K5-34 THERMAL COEFFICIENT OF RESISTANCE IN COPPER |
| 3 |
K5-36 RESISTORS AT LN TEMPERATURE - LIGHT BULB INDICATOR |
| 5 |
K5-43 NON-OHMIC DEVICE - V VS. I |
| 1 |
K5-44 NON-OHMIC DEVICE - LIGHT BULB |
| 3 |
K6-01 SERIES AND PARALLEL LIGHTS - TWO BULBS |
| 2 |
K6-02 SERIES AND PARALLEL LIGHTS - FIVE BULBS |
| 2 |
K6-11 CIRCUIT PARADOXES |
| 2 |
K6-21 HEATING IN CURRENT-CARRYING WIRE |
| 1 |
K6-22 ENERGY CONVERSION - IMMERSION HEATER |
| 3 |
K6-23 HOT DOG COOKER - 110 VAC |
| 1 |
K6-35 VOLTAGE DIVIDER |
| 4 |
K6-51 KIRCHOFF'S LAWS |
| 6 |
K7-11 RC CIRCUIT - RC TIME CONSTANT - |
| 3 |
K7-12 RC CIRCUIT - RC TIME CONSTANT - PROJECTION METERS |
| 2 |
K7-21 RLC CIRCUIT - 10 KHZ - RESONANCE |
| 1 |
K7-42 BARRICADE FLASHER |
| 4 |
K7-43 RELAXATION OSCILLATOR - NEON LAMP |
| 1 |
M8-31 LIQUID CRYSTALS |