With the counterweights in place, you can now safely cross the bridge and enter the hut on the the hill. Inside you can find that Dr. Brain's flair for strange decorations knows no bounds. Click on the screen of the computer to start the mask match puzzle

Match Puzzle

For this puzzle, you are asked to find 5 sets of 3 matching shapes. For Novice, Standard, and Expert difficulties, you must sort through various shapes, hieroglyphics, and masks respectively. Some may jump out at you, especially on Novice difficulty, but otherwise, many of the objects tend to look similar. To keep from getting lost, take a systematic approach. Start at one of the corners and go through the shapes one by one until you have either found two exact matches or have examined all the shapes.

For the Standard and Expert difficulties, to tell the shapes apart, break each one up into pieces. When dealing with the masks, look at the hair, the eyes, and the mouth individually. For instance, look at the figure at the top right of the example given and notice that its hair is wavy and yellow. If you look at this feature alone, over half of the remaining masks are eliminated. Next, notice that it has a bone through its nose and its eyes are big and green. Go through the figures with wavy yellow hair and look for something that matches. As you go through them, you'll notice that there are no matches, so you can eliminate this mask as a possibility.

When you've correctly matched three figures, rectangles of the same color will form around them. This separates them from the rest, meaning that there will be three less figures that you have to examine. So the puzzle gets a little easier with each set you find.

If you manage to find all 5 sets of 3 figures, you will be awarded with a small gold key. Grab the key from the totem pole and use it on the bookshelf in the back of the room to open the bookshelf puzzle.

Bookshelf Puzzle

It seems as though someone has misplaced all of Dr. Brain's books. Either the maid couldn't speak English or she just hadn't recently brushed up on her Chinese Gods. Either way, it's up to you to get them straight. Mouse over the books with letters on them to see what their subject is. Then move each subject to it's proper category, labeled on the shelf. Listed below are the possible subjects and their corresponding categories:

Novice

Animals

Category Subjects
Birds Robin; Crow; Jay; Raven; Eagle; Ostrich; Emu; Owl; Duck; Goose; Vulture; Macaw; Flamingo
Fish Pike; Trout; Perch; Carp; Catfish; Bass; Marlin; Halibut; Seahorse; Salmon; Tuna; Turbot; Eel
Insects Ant; Aphid; Bee; Butterfly; Cicada; Cricket; Earwig; Flea; Katydid; Wasp; Termite; Silverfish; Louse
Mammals Tiger; Rabbit; Cow; Camel; Dog; Rat; Monkey; Kangaroo*; Bat; Seal; Rhinoceros; Whale; Armadillo
Reptiles Iguana; Gecko; Gila Monster; Thorn Devil; Tortoise; Turtle; Crocodile; Snake; Chameleon; Alligator; Tuataras; Lizard; Caiman
• yes, kangaroos are marsupials, but marsupials are a subclass of mammals.

Body Systems

Category Subjects
Circulatory Heart; Veins; Arteries; Blood; Plasma; Platelets; Capillaries; Venules; Arterioles
Digestive Stomach; Intestine; Mouth; Esophagus; Colon; Salivary Glands; Pancreas; Gall Bladder; Liver
Nervous system Neurons; Nerves; Receptors; Effectors; Brain; Spinal Cord; Axon; Dendrites; Synapse
Respiratory Lungs; Diaphragm; Alveoli; Chest Wall; Pharynx; Larynx; Trachea; Cilia; Bronchi
Skeletal Tarsal; Phalanges; Fibula; Tibia; Femur; Carpal; Sacrum; Pubis; Ulna

Gods

Category Subjects
Aztec Tonacatecutli; Tonacacihuatl; Tezcatlipoca; Meztli; Huitzilopochtli; Tlaloc; Tzinteotl; Tlazolteotl; Michtlantecutli; Quetzalcoatl
Celtic Dagda; Danu; Lug; Branwen; Morrigan; Manannan; Goibniu; Macha; Taranis; Brigit
Chinese Yu-huang; T'ien Hou; Ch'ang-o; Huang-ti; Lung-wang; Sheng-mu; Yen-wang; Wen-ch'ang; Shen-nung
Egyptian Amon-Re; Anubis; Hathor; Horus; Isis; Osiris; Ptah; Thoth; Mont
Greek Aphrodite; Apollo; Athena; Artemis; Demeter; Ares; Hera; Persephone; Poseidon; Prometheus; Zeus
Indian Indra; Lakshmi; Surya; Soma; Varuna; Parvati; Kama; Yama; Rudra; Krishna
Mayan Hun-Ahpu; Ixazaluoh; Itzamna; Hurakan; Chac; Humahau; Kukulcan
Norse Balder; Frigg; Loki; Volund; Frey; Odin; Aegir; Thor; Hel
Roman Juno; Pluto; Ceres; Cupid; Diana; Minerva; Jupiter; Mars; Mercury; Neptune; Vulcan
Sumerian Anu; Innini; Babbar; Nanna; Enlil; Enki; Ishtar; Ereshkigal; Nabu; Shamash
West African Nyame; Asase Yaa; Lisa; Tano; Avlekete; Orunmila; Ananse; Xevioso; Olokun

Musical Instruments

Category Subjects
Brass Cornet; Trumpet; French Horn; Bugle; Trombone; Tuba
Percussion Bells; Maracas; Gongs; Drums; Xylophone; Timpani
String Violin; Cello; Viola; Guitar; Harp; Lute
Woodwind Flute; Oboe; Bassoon; English Horn; Saxophone; Clarinet; Piccolo

Standard

Geography

Category Subjects
Africa Morocco; Tunisia; Algeria; Libya; Egypt; Sudan; Chad; Niger; Nigeria; Ghana; Ivory Coast; Zaire[1]; Angola; Zambia; Uganda; Ethiopia; Botswana; South Africa; Zimbabwe
Asia China; India; Mongolia; Burma[2]; Laos; Vietnam; Japan; North Korea; South Korea; Philippines; Cambodia; Malaysia; Sri Lanka; Nepal; Iran; Iraq; Afghanistan; Turkey; Lebanon; Israel; Saudi Arabia; Thailand
Europe Norway; Sweden; Finland; Poland; Germany; France; Austria; Spain; Switzerland; Italy; Portugal; Hungary; Yugoslavia[3]; United Kingdom; Ireland; Denmark; Russia; Romania; Bulgaria; Czechoslovakia[4]; Netherlands
North America Canada; United States of America; Mexico; Guatemala; El Salvador; Cuba; Panama; Nicaragua; Honduras; Costa Rica; Belize
South America Argentina; Chile; Brazil; Venezuela; Colombia; Ecuador; Peru; Bolivia; Paraguay; Uruguay
Deserts Death Valley; Gobi; Great Basin; Kalahari; Kara Kum; Kyzyl Kum; Mojave; Negev; Sahara; Sahel; Takli makan; Thar; Atacama; Arabian
Lakes Ontario; Caspian Sea; Superior; Victoria; Aral Sea; Titicaca; Huron; Michigan; Tanganyika; Baikal; Nyasa; Albert; Balkhash; Bangweulu; Chad; Erie; Geneva; Mead; Tahoe
Mountains Andes; Everest; Kilimanjaro; Matterhorn; Fuji; McKinley; Rainier; Saint Helens; Shasta; Whitney; Olympus; Vesuvius; Popocatepet; Jungfrau; Mauna Loa; Mauna Kea; Etna
Rivers Amazon; Danube; Nile; Congo; Ganges; Hudson; Jordan; Mississippi; Niger; Potomac; Rhine; Rio Grande; St. Lawrence; Seine; Thames; Volga; Yangtze; Zambezi
1. Zaire is a former name of Democratic Republic of the Congo.
2. Also known as Myanmar.
3. Former country composed of Serbia, Montenegro, Croatia, Kosovo, and Bosnia and Herzegovina.
4. Former aggregation of Czech Republic and Slovakia.

Composers

Category Subjects
Irving Berlin Easter Parade; God Bless America; White Christmas; Alexander's Ragtime Band; All Alone; Blue Skies; Always
George M. Cohan I'm a Yankee Doodle Dandy; Give My Regards to Broadway; You're a Grand Old Flag; Mary's a Grand Old Name; Harrigan; Over There
Gershwin: Swanee I Got Rhythm; Love Walked In; Embraceable You; Soon; S Wonderful
Jerome Kern Bill; All the Things You Are; Make Believe; Ol' Man River; Smoke Gets in Your Eyes
Cole Porter Begin the Beguine; Night and Day; I've Got You Under My Skin; You're the Top; Anything Goes
Rodgers The Lady Is a Tramp; Falling in Love With Love; People Will Say We're in Love; Some Enchanted Evening; Hello, Young Lovers
Schubert Ave Maria; Death and the Maiden; Serenade; The Trout; Who Is Sylvia?
Paul Simon The Sounds of Silence; Homeward Bound; Mrs. Robinson; Bridge Over Troubled Water; Loves Me Like a Rock

Astronomy

Category Subjects
Constellations Delphinus; Cetus; Pegasus; Aquarius; Orion; Perseus; Andromeda; Cassiopeia; Hercules; Ursa Major; Cepheus
Moons Phobos; Deimos; Triton; Nereid; Callisto; Europa; Io; Ganymede; Titan; Oberon; Charon
Planets Mercury; Venus; Earth; Mars; Jupiter; Saturn; Uranus; Neptune; Pluto
Space Shuttles Luna; Ranger; Apollo; Pioneer; Mariner; Helios; Venera; Voyager; Giotto; Galileo
Stars Sirius; Polaris; Betelgeuse; Sun; Alpha Centauri; Arcturus; Vega; Capella; Altair; Pollux

Painters

Category Subjects
Dali The Three Sphinxes of Bikini; Fifty Abstract Paintings in Which One Sees...; Hallucinogenous Bullfighter; The Persistence of Memory
Kandinsky Storeys; White Stroke; Colorful Ensemble; Gorge Improvisation
O'Keefe Jack in the Pulpit #2; Red Poppy No. VI; Petunia and Coleus; Black Iris II
Picasso Girl Before a Mirror; Woman's Head with Self Portrait; Three Musicians; The Dream (1932)
Jackson Pollock Composition with Pouring II; Overall Composition; Convergence #10; The Moon Woman Cuts the Circle
Van Gogh The Night Cafe; Sunflowers; Fishing Boats on the Beach at Saintes-Maries; Road with Cypress and Stars; Van Gogh's self portrait

Expert

Authors

Category Subjects
Mark Twain Adventures of Tom Sawyer; Prince and the Pauper; Adventures of Huckleberry Finn; A Connecticut Yankee in King Arthur's Court; Life On The Mississippi
William Faulkner A Fable; The Reivers; The Sound and the Fury; Requiem for a Nun; The Unvanquished; A Rose for Emily; Absalom, Absalom!; Go Down, Moses
Leon Uris Battle Cry; Exodus; The Angry Hills; Mila 18; Topaz; QB VII; Trinity; The Haj
Jules Verne Around the world in 80 days; twenty thousand leagues under the sea; journey to the center of the earth; From the Earth to the Moon; Five Weeks in a Balloon
R.L. Stevenson Treasure Island; Kidnapped; David Balbour; New Arabian Nights; The Master of Ballantrae; The Strange Case of Dr. Jekyll and Mr. Hyde
John Steinbeck East of Eden; Tortilla Flat; Cannery Row; Sweet Thursday; In Dubious Battle; Of Mice And Men; The Winter Of Our Discontent; Travels With Charley; The Grapes Of Wrath
Judy Blume Are You There, God? It's Me, Margaret; Otherwise Known as Sheila the Great; Then Again, Maybe I Won't; Tales of a Fourth Grade Nothing; Blubber; Superfudge
Jane Austen Pride and Prejudice; Emma; Sense and Sensibility; Northanger Abbey; Mansfield Park
Dr Seuss How the Grinch Stole Christmas; The Cat in the Hat; Hop on Pop; Green Eggs and Ham; You're Only Old Once; Horton Hears a Who; The Lorax; The Sneetches
Edgar Allen Poe Morella; Ligeia; Shadow; The Purloined Letter; The Tell-Tale Heart; Tales of the Grotesque and Arabesque; The Pit and the Pendulum; The Masque of the Red Death; The Gold-Bug; The Fall of the House of Usher
James Michener Tales of the South Pacific; Sayonara; Hawaii; Centennial; Chesapeake; Texas; Poland; The Source; The Covenant
Rudyard Kipling: Kim, Wee Willie Winkie and Other Stories; Captain Courageous; Just So Stories; The Jungle Book
Stephen King Carrie; Christine; Cujo; The Stand; The Firestarter; Pet Sematary; The Dead Zone; The Tommyknockers
Ernest Hemingway The Old Man and the Sea; The Sun Also Rises; A Farewell to Arms; Death in the Afternoon; For Whom the Bell Tolls; The Snows of Kilimanjaro, and other stories
Charles Dickens Great Expectations; Bleak House; David Copperfield; The Old Curiosity Shop; A Tale of Two Cities; Oliver Twist; A Christmas Carol
Beverly Cleary Runaway Ralph; Beezus and Ramona; Henry Huggins; Dear Mr. Henshaw; The Mouse and the Motorcycle
Pearl Buck The Good Earth; Dragon Seed; Imperial Woman; The Living Reed; East Wind: West Wind; My Several Worlds; A House Divided; A Bridge for Passing
Louisa May Alcott Little Women; Little Men; Jo's Boys; An Old-Fashioned Girl; Eight Cousins

Habitats

Category Subjects
Temperate Forest Moose; Wood Frog; Otter; Beaver; Muskrat; Raccoon; Skunk; Porcupine; Opossum; Woodchuck; Chipmunk; White-tailed Deer; Snapping Turtle; Wild Boar; Koala; Echidna; Flying Squirrel; Garter Snake
Tropical Forest Black Howler Monkey; Spider Monkey, Coati, Iguana, Two-toed Sloth, Ocelot, Tree Boa Constrictor; Axis Deer, Chevrotain; Tapir; Gibbon; Bongo; Jaguar; Leopard; Orangutan
Polar Region Musk Ox; Arctic Hare; Polar Bear; Emperor Penguin; Caribou; Walrus; Collared Lemming; Ermine
Ocean Octopus; Whale; Manatee; Shark; Copepod; Starfish; Limpet; Jellyfish; Saltwater Crocodile
High Mountains Vicuna; Yak; Bighorn Sheep; Snow Leopard; Himalayan Ibex; Chinchilla; Giant Panda; Marco Polo Sheep
Grassland Ostrich; Giraffe; Aardvark; Zebra; Gnu; Pronghorn; Kudu; Blackbuck; Hippopotamus; Kangaroo; Prairie Dog; Elephant
Desert Dingo; Scorpion; Camel; Dromedary; Saiga; Gila Monster; Kit Fox; Bobcat; Coyote; Muledeer; Pocket Mouse; Kangaroo Rat; Cacomistle; Sidewinder; Chuckwalla

Habitats

Category Subjects
South America Amazon River; Lake Titicaca; Andes Mountains; Cape Horn; Galapagos Islands; Angel Falls; Atacama Desert;

Lake Maracaibo; Tropical Rain Forest

North America Rocky Mountains; Death Valley; Everglades; Grand Canyon National Park; Great Lakes; Great Salt Lake; Klondike; Mississippi River; Niagara Falls; Painted Desert; Rio Grande; Yosemite National Park; Yukon River
Europe Volga; Danube; Rhine; Dardanelles; English Channel; Alps; Baltic Sea; Bay of Biscay; Aegean Sea
Australia Botany Bay; Coral Sea; Darling River; Great Barrier Reef; Great Victoria Desert; Lake Eyre; Lake Torrens; Mount Kosciusko; Murray River
Asia Mt Everest; Pamir Knot; Altai Mountains; Tigris; Euphratesl Taklimakan Desert; Gobi Desert; Jordan
Antarctica Horlick Mountains; Whitmore Mountains; Filchner Ice Shelf; Berkner Island; Ross Sea; Prydz Bay; Ross Ice Shelf; Mertz Glacier
Africa Nile River; Mt. Kilimanjaro; Victoria Falls; Cape of Good Hope; Great Rift Valley; Suez Canal; Sahara Desert; Congo River; Canary Islands

Playwrights

Category Subjects
Thornton Wilder Our Town;The Bridge of San Luis Rey; The Skin of Our Teeth; The Angel That Troubled the Waters; The Long Christmas Dinner; The Matchmaker
Tennessee Williams The Glass Menagerie; A Streetcar Named Desire; Cat on a Hot Tin Roof; The Rose Tattoo; Camino Real; Sweet Bird of Youth; The Night of the Iguana
JB Shaw Pygmalion; Candida; The Devil's Disciple; Caesar and Cleopatra; Man and Superman; Major Barbara; Androcles and the Lion; Heartbreak House; The Doctor's Dilemma
Shakespeare King Lear, Hamlet, Macbeth, Othello, Much Ado About Nothing; As You Like It; Anthony and Cleopatra; All's Well That Ends Well; A Midsummer Night's Dream; The Taming of the Shrew; The Merchant of Venice; Romeo and Juliet
Moliere The Would-Be Gentleman; The School for Wives; Tartuffe, or The Imposter; Don Juan; The Misanthrope; The Miser; The Learned Ladies
Arthur Miller The Price; The Crucible; After the Fall; Incident at Vichy; Death Of A Salesman; A View from the Bridge; All My Sons
Henrik Ibsen Ghosts; Brand; Peer Gynt; An Enemy of the People; The Wild Duck; Hedda Gabler; A Doll's House
Chechov The Cherry Orchard; The Seagull; Uncle Vanya; Three Sisters; Ivanov
Edward Albee A Delicate Balance; Who's Afraid of Virginia Woolf?; Tiny Alice; All Over; Seascape; The Zoo Story; The Death of Bessie Smith; The American Dream
Neil Simon Come Blow Your Horn; Barefoot in the Park; The Odd Couple; Last of the Red Hot Lovers; Chapter Two; Brighton Beach Memoirs; Biloxi Blues; Plaza Suite; The Good-bye Girl

Poems

Category Subjects
Walt Whitman I Celebrate; O Captain! My Captain!; Out of the Cradle Endlessly Rocking;A Noiseless Patient Spider; Earth, My Likeness; Are You the New Person Drawn Toward Me?; Roots and Leaves Themselves Alone; Not Heat Flames Up and Consumes; After the Dazzle of Day; Song of the Open Road
Shakespeare Venus and Adonis; The Rape of Lucrece; The Passionate Pilgrim; The Phoenix and Turtle; A Lover's Complaint
Edgar Allen Poe The Raven, Israfel; Eldorado; The Happiest Day, the Happiest Hour; Annabel Lee;To My Mother; The City in the Sea; To One in Paradise; The Haunted Place
Ogden Nash Oh, Stop Being Thankful All Over the Place; The Terrible People; And Three Hundred and Sixty-Six in Leap Year; Oh, Please Don't Get Up!; A Caution to Everybody; Portrait of the Artist As a Prematurely Old Man; Reflections on Ice-Breaking
Emily Dickenson The Soul Selects Her Own Society; My Life Closed Twice Before Its Close; Because I Could Not Stop for Death; After Great Pain a Formal Feeling Comes; A Shady Friend for Torrid Days; I Heard a Fly Buzz When I Died; I Taste a Liquor Never Brewed; I Took My Power in My Hand; The Wind Tapped Like a Tired Man; Step Lightly on This Narrow Spot
EE Cummings All in Green Went My Love Riding; Spring is Like a Perhaps Hand; No Man, if Men Are Gods; What if a Much of a Which of a Wind; My Sweet Old Etcetera; Always Before Your Voice My Soul; Pity This Busy Monster, Manunkind
Stephen Crane I Stood Upon a High Place; I Saw a Man Pursuing the Horizon; The Wayfarer; A Youth in Apparel That Glittered; A Learned Man; A Man Saw a Ball of Gold in the Sky; There Was a Man With a Tongue of Wood
WH Auden The Labyrinth; Perhaps; Lakes; Woods; The Trial; Under Sirius; In Praise of Limestone; The Unknown Citizen; The Shield of Achilles
Longfellow The Cross of Snow; Evangeline; Tales of a Wayside Inn; The Courtship of Miles Standish; The Song of Hiawatha
Robert Frost Fire and Ice; Acquainted with the Night; The Hill Wife (The Impulse); To Earthward; Stopping by Woods on a Snowy Evening; On Looking Up by Chance at the Constellations; The Witch of Coos; The Silken Tent

Counterweight Puzzle

As the last book is set into place, the book's covers disappear and the bookshelf slides aside to reveal the secret back room. Upon stepping inside, you find that among the eclectic assortment of interactive decorations is an elevator and a drinking fountain. It looks like Dr. Brain's giving you a refreshment break! Let's see here, what are the choices? Water, alcohol? and... mercury? What?! Is Dr. Brain trying to poison you? No, of course not, it's just his counterweight puzzle. Slip on your gloves and fume mask and jump right in.

~ Water Mercury Alcohol
Cup 0 lb, 8 oz 7 lb, 1 oz 0 lb, 6 oz
Quart 2 lb, 0 oz 28 lb, 4 oz 1 lb, 8 oz
Gallon 8 lb, 0 oz 113 lb, 0 oz 6 lb, 0 oz

The object of this game is to pour exactly enough liquid to equal the weights at the bottom using only the measurements and liquids given. The red number next to the liquid's symbol shows how many dispenses this liquid has. It doesn't matter if the amount of liquid dispensed is an ounce or a gallon, it will only distribute liquid this many times. If too much is weight is added to any one of the three compartments, the whole thing drains and you must start over with a different set of numbers. With only a limited amount of liquid available, the challenge here is to make sure that you make the most efficient use of what you are given.

On Novice and Standard levels, each of the weights will correspond to one of the liquids, although not necessarily the one it is under. What this means is that only one liquid will be used per weight. More often than not, the heaviest weight will correspond to mercury, the second heaviest to water, and the lightest to alcohol. In these cases, once you have identified which liquid goes with which weight, add the largest container of that liquid that you can without going over. When you can't add any more of that size, start adding the next size down until the numbers magically get to 0 pounds and 0 ounces.

The Expert difficulty of this puzzle is an entirely different game. First of all, each of the weights at the bottom will need to be reached using more than one liquid. Additionally, if too much weight is put onto one side of the counterweight, the thing will tilt and spill over. If this occurs, the game will restart with new numbers. This means that you can't just focus on one weight at a time.

The first thing to look for are the weights that require mercury. These are fairly obvious, as the mercury is ridiculously heavy. A quart of mercury weighs in at 28 pounds, 4 ounces and a gallon weighs a whopping 113 pounds! That's slightly heavier than the average couch. Anyway, you will probably never need to use the gallon of mercury. If a weight is 30 pounds or more, add quarts of mercury until it drops under 28 pounds. Remember that if you add too much weight to the side of the counterweight, it is prone to spilling. Thankfully, these weights usually come in pairs on the left and right side. See the picture above for an example of this. If this is the case, you will have to go back and forth adding to the left and right to keep the counterweight from tipping over. Once all weights are below 28 pounds, there is likely little mercury left. To determine which weights need cups of mercury, check the ounces. Ignoring the pounds, you want the ounces to be even. Any weight that has an odd number of ounces will require at least one cup of mercury. Once this is achieved, if any of the weights are over 14 pounds and you have at least 2 portions of mercury left, go ahead and add 2 cups of mercury to that weight. In the example shown, notice the weight on the left. The ounces read "6", which is even, but there is 16 pounds left. With two cups of mercury, the weight drops to 2 lbs, 4 oz.

When the mercury has run out, all you have to worry about are the water and alcohol dispensers. Look at the chart above that lists the weights of each volume of each substance and take notice of the ounce possibilities of water. Any give volume of water will add 0 or 8 ounces. This means that unless the weight left has either 8oz or 0oz, water alone will not be able to get it to 0 exactly. Therefore, any weight that does not have 0 or 8 for the ounces must be given cups of alcohol until it does.

There are multiple solutions to this puzzle, and there may be some liquid left when all of the weights reach zero. Once all of the ounces read 8 or 0, there are a number of different paths possible to the solution. At this point, you are on your own. There are several general rules of thumb that can help you, such as if the pounds is odd and the ounces is "8", add a quart of alcohol to get an even number for the pounds and 0 for the ounces.

~ Water Mercury Alcohol
Cup 0 lb, 8 oz 7 lb, 1 oz 0 lb, 6 oz
Quart 2 lb, 0 oz 28 lb, 4 oz 1 lb, 8 oz
Gallon 8 lb, 0 oz 113 lb, 0 oz 6 lb, 0 oz

Elevator Puzzle

Now that the counterweight is set, the elevator should be ready to go, right? Nope. The hut's elevator seems to still be broken. To get the elevator running, the correct gear ratio must be found so the mouse in the hamster wheel doesn't get overwhelmed. If the ratio is too large, the elevator will plummet to the bottom. If the ratio is too small, the elevator will hurtle into the ceiling. Though this puzzle involves a little bit of math, it is one of the easiest puzzles to solve, even on Expert difficulty.

The object of this puzzle is to find the gear on top and the gear on bottom that are in the correct ratio, that is the gear on top multiplied by the correct number will equal the one on bottom. The first step is to find the ratio, or the number that the top one will be multiplied by to reach the bottom one. On both Novice and Standard difficulties, this is done by dividing the weight of the counterweight (on the right) by the weight of the elevator (on the left). In the example shown, this would be 2290 divided by 458, which is an even 5. This is the ratio. On Expert difficulty, subtract the weight of the counterweight by the weight of the elevator and divide the difference by 25 to get the ratio.

Once you have the ratio, multiply each of the numbers on the top by this number. If the product of the ratio and the top gear is the same as any of the ones on the bottom, you have found the two gears. If the product is not on the bottom, try another gear. In the end, it all comes down to trial and error. In the example shown, we have found that the ratio is 5. If 13 is the top gear, then the bottom gear would need to be 13*5, or 65. 65 doesn't appear in the bottom, so we check the next top gear, 15. If the top gear is 15, then the bottom gear would need to be 15*5, or 75. This number does appear on the bottom, so the correct two gears to use are 15 and 75.

When you have found the two gears that are in the correct ratio, click the red arrow in the center to test the elevator. If all goes well, the elevator will run smoothly down the shaft and grant you access to Dr. Brain's underground laboratory.