JOURNAL

Instruments

Antique scientific instruments: how to identify type and period

Material, scales, optics, mounting and the maker's signature – how an instrument gives away its age.

Storage

How to store a paper collection so it does not fade

Light, humidity and the wrong plastic – the three things that ruin stamps and postcards for good.

Stamps

Stamps of the world: how the catalogue works

271 countries and 80,472 images: finding an issue in three steps, and what themes are for.

Cars

How the shape of the car changed after 1886

From motor carriage to electric platform – five turning points across 300 models.

Clocks

Antique clocks: identifying type and age

Tower, mantel, pocket and precision movements – the clues that tell them apart and date them.

Rockets

Launch vehicles: five generations of rockets

Early experiments, orbital, crewed, heavy and reusable – how a timeline of 203 launchers is built.

Robots

Robots: six families of real machines

Industrial, research, space, humanoid, medical and household – how to read a timeline of 230 machines.

Collecting

How to choose a collecting theme

Four questions before the first purchase and a tour of the open directions.

Collecting

You inherited a collection: what now

The order of operations: clean nothing, sort, list, identify – and only then decide.

Plants

Botanical illustration: how to read an old plate

Florilegium, herbal and scientific plate – three genres and the elements that identify a sheet.

Ukiyo-e

Ukiyo-e: how a Japanese print is made

Genres, printing from several blocks, signatures and seals – and early versus late impressions.

Miniatures

Portrait miniatures: carrying a face before photography

Ivory, enamel and the locket – what a miniature is made of and what gives it value.

Stained glass

Stained glass: building a picture out of light

Glass, lead, painting and firing – what a window is made of and what carries value.

Masks

Masks: four reasons to cover a face

Theatre, ritual, burial and ornament – why masks were made and how to tell them apart.

Stamps

How to start collecting stamps without spending

Six steps from an old envelope to a sorted collection – no album, no catalogue, no purchases.

Guides

Original or copy: reading paper and metal

A halftone dot grid on paper and soft relief on metal – how a copy gives itself away.

Stamps

How to identify an old stamp in five steps

Country, denomination, date clues, perforation, printing – five readings that lead to a catalogue number.

Coins

Cleaning old coins: why collectors do not

Baking soda, vinegar, cola, toothpaste – why every household method costs more than it gains.

Coins

Coin condition explained without the jargon

Five levels in plain language, the high points that wear first and why the fields decide more than the design.

Guides

How to see a watermark without special fluid

Four safe ways to read a watermark on paper, and why fluid should be your last resort.

Stamps

First day covers: what they are and what decides value

An envelope cancelled on the stamp's first day – what makes one collectible and why most are common.

Coins

How to start a coin collection from a drawer

Six steps from a drawer of change to a sorted collection – no purchases and no price guide.

Stamps

Mint versus used stamps: what actually changes

Mint is not automatically better: what each state means and when a cancelled stamp is the better object.

Stamps

Hinges and mounts: why a hinge costs you

A folded paper tab that leaves a permanent mark: how hinges work and what to use instead.

Banknotes

Banknote condition: how paper is read

Folds, corners, body and edges – how paper money is graded and why one fold changes everything.

Guides

Errors and varieties: what actually counts

An error happens once, a variety repeats, damage is neither – and most finds are the third.

Guides

Photographing coins and stamps without glare

Glare is a lighting problem, not a camera one: where to put the light and how to make relief readable.

Postcards

Dating an old postcard and what makes it collectable

The back dates the card: divided line, stamp box, imprint and postmark, and what makes one collectable.

Guides

Storing coins and metal objects at home

Contact, moisture and the wrong plastic – the three enemies of metal, and the cheap way to stop them.

Guides

Preparing a collection for valuation

Sort, list, photograph, leave alone – how to make a collection legible before anyone values it.

Stamps

Perforation: how it is measured and why it exists

Counted over two centimetres, not guessed – how perforation is measured and why it changes the stamp.

Guides

Cataloguing a collection so it survives you

Nine columns that fit any material, and why the number belongs on the envelope, not the object.

Guides

Collecting with children: what actually works

A theme they chose, objects they may touch and a goal that can actually be finished.

Stamps

Postal history: collecting the journey, not the stamp

The route, the rate and the handstamps – why the envelope often outranks the stamp on it.

Banknotes

Spotting a fake collector banknote

Paper, printing, watermark, detail – four checks that separate a reproduction from a real note.

Coins

Why coins turn green, and what to do about it

Stable green protects, powdery green destroys – how to tell them apart and stop the second.

Stamps

What actually makes a stamp rare

Survival, not age: six things that make a stamp scarce and four assumptions that mislead.

Coins

Toning on silver coins: natural, cabinet and artificial

Slow, layered and edge-first – how natural toning differs from colour added last week.

Guides

Arranging a collection in an album

An album is an argument, not a container: four ways to order it and why gaps matter.

Guides

Collecting on a budget: where the interest hides

Six directions where inexpensive material is genuinely interesting, and where money is wasted.

Stamps

Which country is this stamp from?

Currency, script, portrait, emblem – six ways to find the country when the name is unreadable.

Stamps

Overprints and surcharges: why they exist

Printing added to a finished stamp – five kinds, and why they are forged more than anything else.

Stamps

Definitives and commemoratives: the real difference

Everyday workhorses versus short one-off issues – and why the plain stamp is often harder.

Stamps

Stamp formats: sheets, blocks, booklets, se-tenant

Single, block, sheet, booklet, coil, se-tenant – six formats, and why splitting one destroys it.

Coins

Mint marks: finding where a coin was struck

A tiny letter that splits one year into two coins – where to look and what it changes.

Coins

Proof and circulation strikes: telling them apart

Mirror fields, frosted relief, sharp rims – four signs that separate a proof from an ordinary coin.

Stamps

Special-purpose stamps: airmail, charity, postage due

Airmail, charity, postage due, official – four purposes that change how a stamp was used.

Coins

The edge of a coin: why it is reeded or lettered

Reeded, plain, lettered, ornamented – what the third side of a coin actually records.

Banknotes

Serial numbers: what a banknote's number tells you

Prefix, sequence, patterns, replacements – how to read the only unique part of a note.

Badges

How an enamel badge is made, and why it matters

Glass fused at heat or paint under lacquer – the difference that decides everything else.

Stamps

Paper and gum: reading the back of a stamp

Thickness, surface, colour, gum state – four readings that split identical-looking stamps.

Guides

Labels that look like stamps but are not

Charity seals, revenues, poster labels, fantasies – stamp-shaped things that never carried mail.

Stamps

Shades: when the same stamp is a different colour

Printing, chemistry or fading – three reasons a stamp changes colour, one of them collectable.

Guides

Repair and restoration: what is acceptable

Stabilise, do not improve – where conservation ends and hidden damage begins.

Guides

Buying from photographs: what an image must show

Both sides, full edges, raking light – the shots a listing must include before you pay.

Guides

Provenance: why an object's history is part of it

Where it came from and who held it – the record that supports everything else about an object.

Guides

Trading duplicates: how exchange actually works

Sort, list, describe honestly – how duplicates turn into the things you are missing.

Guides

Sorting a mixed lot: the first hour

Six passes in an hour – the order that turns an unreadable box into something you can read.

Stamps

Postal rates: why denominations look so odd

Every odd value paid something specific – how rates explain what was printed and when.

Architecture

Architectural styles in chronological order: ten eras with examples

From the Parthenon to the Burj Khalifa: the years of each style, three identifying features and example buildings from the collection.

Architecture

The pyramids of Giza: who built them, how, what was found inside and what people argue about

The workers' town, the Diary of Merer, voids seen with muons, and a separate section of theories and conspiracy claims.

Architecture

How were the pyramids built? Step by step, with the evidence and the theories

Quarrying, sledges on wet sand, the ramp found in 2018, alignment to the stars and the size of the workforce, with a separate section on the theories.

Architecture

Romanesque vs Gothic architecture: how to tell them apart in five looks

Round arch vs pointed arch, thick walls vs flying buttresses, small windows vs stained glass, with dates and church examples.

Architecture

Gothic architecture: characteristics, examples and how to read a cathedral

The seven characteristics with the buildings that show each, the three phases from Early to Flamboyant, and famous examples in Europe and the US.

Architecture

Baroque architecture: characteristics, examples and how it differs from Gothic and Rococo

Eight characteristics with the buildings that show each, from Bernini to Rastrelli; how Baroque differs from Gothic and Rococo, and Baroque in the Americas.

Architecture

Art Nouveau vs Art Deco: the difference in architecture, with buildings to compare

Curves from nature vs zigzags from machines, 1890–1914 vs 1920–1940, with a comparison table and buildings from Casa Batlló to the Chrysler Building.

Architecture

Brutalist architecture: characteristics, examples, and why people love and hate it

What the word means, six characteristics, the best examples in the US, UK and the USSR, why it was hated and why it is back.

Architecture

Neoclassical architecture: characteristics and examples, from the Capitol to Saint Petersburg

Seven characteristics, why America chose the style, how it differs from Greek Revival, Federal and Beaux-Arts, with examples from the Capitol to Saint Isaac's.

Architecture

Mid-century modern architecture: characteristics, examples and the houses that started it

Eight characteristics, the houses that defined it from Farnsworth to the Case Study program, the public landmarks, and why the style is back.

Architecture

Stonehenge: how it was built, what it was for, and every theory from Merlin to aliens

Who built it and when, where the stones came from, what it was for by the latest digs, and every theory from Merlin to aliens with a verdict on each.

Architecture

Göbekli Tepe: how old it is, what the carvings mean, and what it changed about history

How the 11,600-year-old enclosures were dated, who built them before farming, what the T-pillars show, the sister sites, and the theories with a verdict on each.

Architecture

Who built Teotihuacan? The city, the pyramids, the tunnel of mercury and the theories

The city of 100,000 the Aztecs found empty, the pyramids, the 200 sacrifices under the Feathered Serpent, the tunnel of mercury, and the theories with a verdict on each.

Architecture

Machu Picchu: the mysteries solved, the ones still open, and how the Incas built it

Who built it and why, the 2021 dating, mortarless walls and hidden drains, why the Spanish never found it, what the skeletons show, and the theories with a verdict on each.

Architecture

Angkor Wat: facts and history, from the largest temple on Earth to the city the jungle took back

Who built it and when, its size, the towers and reliefs, how the sandstone was moved, the city of a million around it seen by lidar, why it fell, and the theories.

Architecture

The oldest temples in the world: a list by age, and the oldest still in use

The oldest sanctuaries on Earth in order of age, how each was dated and what it was for, plus the oldest temples still in use today.

Architecture

Mayan vs Egyptian pyramids: size, age, purpose and why they look alike

Age 2,500 years apart, the one bigger than Giza, tombs inside vs temples on top, steps vs smooth sides, and whether the two were connected.

Architecture

How old is the Sphinx? The age debate, the evidence on both sides, and the theories

The mainstream date and its evidence, the water-erosion argument and the replies, what it is made of, who restored it, the Dream Stele and the hall of records.

Architecture

Architectural styles of American houses: how to identify 16 styles from Colonial to Mid-century

Sixteen styles in order, from Colonial to Mid-century, each with dates, three identifying features and the regions where you find it.

Architecture

Renaissance architecture: characteristics, examples and the buildings that changed everything

Seven characteristics with the building that shows each, the three phases, the spread across Europe, the difference from Gothic and Baroque, and Palladio's road to America.

Architecture

Roman architecture: characteristics, examples, and how the Pantheon's dome was built

Seven characteristics with the buildings that show each, how the Pantheon's dome was built, the Colosseum, aqueducts and baths, and the difference from Greek.

Architecture

Ancient Greek architecture: characteristics, examples, and why the Parthenon was built

The three orders, the temple plan and its optical tricks, theatres and stoas, why the Parthenon was built and how the temples were constructed.

Architecture

Romanesque architecture: characteristics, examples, and why churches looked like fortresses

Seven characteristics with the building that shows each, why the style spread with pilgrims and monks, the regional schools, Richardsonian Romanesque in America, and the difference from Gothic.

Architecture

Victorian architecture: the styles, characteristics and how to tell a Victorian house

Why it is a period, not a style; the seven styles inside it; the marks of a Victorian house; iron, glass and the railway; the landmarks; and the American version.

Architecture

Byzantine architecture: characteristics, examples, and how Hagia Sophia's dome stays up

Seven characteristics with the buildings that show each, how Hagia Sophia was built and why its dome fell, the spread to Venice, the Caucasus and Russia, and the American revival.

Architecture

Art Deco architecture: characteristics, examples, and the American cities that own the style

Eight characteristics with the buildings that show each, the zoning law that shaped the skyscraper, Chrysler and Empire State, Miami Beach, Streamline Moderne and the difference from Art Nouveau.

Architecture

Who built Petra, and why? The Nabataeans, the Treasury, the water system and the theories

The Nabataean traders who carved a capital into the canyon, what the Treasury really is, how the city was watered, why it was abandoned, the Bible, and the theories.

Architecture

Who built the Colosseum, and why? Facts, history, and how 50,000 people got in and out

Vespasian and the spoils of Jerusalem, eight years of construction, how 50,000 people moved, what happened in the arena, what destroyed it, and the myths.

Architecture

How were cathedrals built in the Middle Ages? Without cranes, so tall, and who paid for it

Who designed and who paid, quarrying and lifting without modern cranes, the treadwheel crane and scaffolds, how vaults and buttresses let them rise so tall, why some fell, and how long it took.

Architecture

The tallest buildings in the world, in order, and the tallest building of every age

The tallest buildings today in order with height, year and city; how tallest is measured; and every record-holder over 4,500 years, from Giza to Dubai.

Architecture

The oldest buildings in the world still standing, in order, and the oldest still in use

The oldest standing buildings by age with how each was dated, the oldest still in use, the oldest wooden building, the oldest house, and the oldest in the Americas and the US.

Architecture

The stones of Baalbek: the largest blocks ever moved, who built the temples, and the theories

The 800-ton trilithon, the 1,650-ton block in the quarry, who built the temples and when, how the Romans moved the blocks, and the theories with a verdict on each.

Architecture

Islamic architecture: characteristics and examples, from the Dome of the Rock to the Taj Mahal

Nine characteristics, the parts of a mosque, the five regional styles from Spain to India with the buildings that show each, and what the style gave to Europe.

Architecture

Japanese architecture: the styles, from Ise and Hōryū-ji to the tea house, the castle and Tadao Ando

Seven principles, the styles in order from Ise and Hōryū-ji to castles, tea houses and the modern masters, with the buildings that show each.

Architecture

Abu Simbel: how two temples were cut into 1,036 blocks and moved uphill to escape the Nile

The rock temples of Ramesses II, the colossi and the solar alignment, and the 1964–1968 relocation in 1,036 blocks to escape Lake Nasser.

Architecture

Karnak Temple: the map, the history and what to see in the largest religious complex of antiquity

A walk through the map from the sphinxes and ten pylons to the 134-column hall, the obelisks and the sacred lake, with who built each part and when.

Architecture

Chichen Itza: the pyramid, the serpent of shadow, the city and what lies under El Castillo

Who built it and when, El Castillo as a calendar, the pyramids inside it and the cenote beneath, the ball court, the observatory, the sacred well and the theories.

Architecture

How were castles built in the Middle Ages? The parts of a castle, the builders and the timeline

From the motte-and-bailey to the concentric fortress, every part of a castle explained, who built them, how long and how much, castles on mountains, and why they ended.

Architecture

Why are churches shaped like a cross? And the difference between a cathedral, a basilica, a church and a chapel

Why the plan is a cross, why churches face east, the parts of a church, and what makes a building a cathedral, a basilica, a church, a chapel, an abbey or a minster.

Architecture

How were Roman roads built, and why does Roman concrete heal itself? The engineering that outlasted the empire

The road layer by layer, the network and its speed, the concrete recipe with volcanic ash and seawater, why harbours grew stronger, and how the self-healing chemistry was found.

Architecture

What is a ziggurat? The Ziggurat of Ur, the Tower of Babel and how Mesopotamia built mountains of brick

What the word means, how they were built of mud brick, what stood on top, the Ziggurat of Ur, Babylon's Etemenanki as the Tower of Babel, and the difference from a pyramid.

Architecture

The first skyscraper in the world, and how skyscrapers are built: from Chicago 1885 to Burj Khalifa

The Home Insurance Building of 1885, why Chicago invented the skyscraper, the steel frame and the elevator, how a tower is built today from foundations to the crown, and the height records.

Architecture

Frank Lloyd Wright houses: Fallingwater, the Robie House, Taliesin, the Usonians, and which ones you can visit

The Prairie houses, Taliesin, Fallingwater, the Los Angeles block houses and the Usonians: what they share, the eight UNESCO sites, and which ones you can walk into.

Architecture

Gaudí buildings in Barcelona: all the works you can see, in order, from Casa Vicens to the Sagrada Família

Casa Vicens, Palau Güell, Park Güell, Casa Batlló, La Pedrera, the Sagrada Família and the smaller works: what each is, how Gaudí built them, and how to see them in a day or two.

Architecture

When will the Sagrada Família be finished? The dates, the towers, the money and why it has taken 140 years

The central tower done in 2026, the Glory facade and the stairway into the 2030s, why it took 140 years, how it is built now, the eighteen towers and what they mean.

Architecture

Who designed the White House and the US Capitol: James Hoban, William Thornton, the competition of 1792 and the history of the Capitol dome

The 1792 competitions, James Hoban and the Dublin house behind the White House, Dr William Thornton's Capitol, Jefferson's secret entry, the 1814 fire, and the cast-iron dome of 1866.

Architecture

Who built the Great Wall of China, why, and how: from the Qin emperor to the Ming brick wall, and what is myth

The Qin, Han and Ming walls, why China built them, how rammed earth and brick walls were made, the real length, whether it worked, and the myths about space and the buried dead.

Architecture

How the Eiffel Tower was built so fast: two years, two months, 18,038 pieces of iron, and why it was meant to be torn down

Koechlin's sketch, the factory-made iron, the caissons in the river mud, the jacks, the climbing cranes, the 1887 protest, the 20-year contract and the radio antenna that kept it standing.

Architecture

How the Taj Mahal was built, step by step: Shah Jahan, Mumtaz Mahal, 22 years, 20,000 workers, and the facts behind the legends

Why it was built, the foundations in the river bank, the brick core and marble skin, the inlay and calligraphy, the leaning minarets, the cost and the workers, and the myths of the black Taj and the blinded craftsmen.

Architecture

The Forbidden City in Beijing: who built it, why it was forbidden, what is inside its 980 buildings, and how to visit

Built 1406–20 for the Yongle Emperor, forbidden to all but the court, 980 buildings on a north-south axis, 24 emperors and the last one, the myths of 9,999 rooms, and visiting today.

Architecture

The Alhambra in Granada: what it is, who built it, the Nasrid palaces, the Court of the Lions, the Generalife, tickets and the legends

The Nasrid dynasty, the Alcazaba, the Comares and Lions palaces, the ceilings and the poems on the walls, the Generalife, 1492 and Charles V, tickets and the best route, and the legends.

Architecture

Notre-Dame Cathedral history timeline: from 1163 to the fire of 2019 and the reopening of 2024

1163 to 2024: the Gothic building and its inventions, the coronations and the Revolution, Hugo and Viollet-le-Duc, the fire of 2019, what was lost, and the five-year rebuild.

Architecture

Why is the Leaning Tower of Pisa leaning? The soft clay, the 199-year build, the 5.5-degree tilt and how engineers stopped it falling

Soft clay and shallow foundations, the tilt from 1178, the pauses that saved it, the built-in curve, the 1990 closure and the soil extraction that pulled it back, and the numbers.

Architecture

St Peter's Basilica facts: the tomb under the altar, 120 years of building, Michelangelo's dome, Bernini's square, the numbers and the myths

The tomb of Peter, Constantine's church, 120 years and five architects, the indulgences and Luther, the dome, the Pietà and the baldachin, the square, the numbers, visiting, and the myths.

Architecture

Borobudur temple history: who built the largest Buddhist monument, how it works as a mountain of stone, why it was abandoned and how it was saved

The Sailendras and the years 780–830, the mountain of stone and its three worlds, the reliefs and the stupas, the abandonment and the jungle, Raffles, the UNESCO rescue, and visiting today.

Architecture

Tikal, Guatemala: facts about the Maya superpower in the jungle, its temples, its war with Calakmul, why it fell, and how to visit

The temples and plazas, the kings and the Teotihuacan takeover, the war with Calakmul, the LiDAR city of 60,000 buildings, the collapse, the rediscovery, and visiting at dawn.

Architecture

Hagia Sophia history: Justinian's church of 537, the dome that fell and was rebuilt, the mosque, the museum and the mosque again

Justinian's five-year church, the dome on pendentives and its collapse and rebuilding, the mosaics, 1204 and 1453, the minarets and Sinan, the museum years, 2020, and the legends.

Architecture

How the Brooklyn Bridge was built, step by step: the caissons, the bends, the Roeblings and fourteen years over the East River

Roebling's plan and death, the caissons and the bends, Washington and Emily Roebling, the towers, spinning the cables, the bad wire, the deck, the opening and the numbers.

Architecture

Golden Gate Bridge history and facts: the strait, the fight to build it, Strauss and Ellis, the four years, the colour, the net and the numbers

The strait and the ferries, the campaign and the lawsuits, Strauss and Ellis, four years of building, the net and the deaths, the colour, the opening, the numbers and the myths.

Architecture

Statue of Liberty history and meaning: the French gift, Bartholdi and Eiffel, the copper skin, the pedestal nobody would pay for, and what the torch, crown and chains mean

The 1865 dinner, Bartholdi and Eiffel, the copper and the iron, the pedestal crisis and Pulitzer, 1886, Emma Lazarus, the green patina, and the meaning of the torch, crown, tablet and chain.

Architecture

How the Hoover Dam was built: diverting the Colorado, the high scalers, cooling 3.25 million cubic yards of concrete, and five years in Black Canyon

Why and where, the diversion tunnels, the high scalers, Boulder City, the cooled concrete columns, the arch-gravity design, the powerhouse, Lake Mead, the deaths, the Art Deco and the numbers.

Architecture

Mount Rushmore history: why four presidents were carved into the Black Hills, how Borglum did it with dynamite, the Lakota claim, and the unfinished mountain

The tourism idea, Borglum, why these four presidents, the Six Grandfathers and the 1868 treaty, fourteen years of dynamite, the moved Jefferson, the Hall of Records, 1941, Crazy Horse, and the disputes.

Architecture

Empire State Building facts and history: 410 days, the race with Chrysler, the airship mast, the 1945 bomber crash, King Kong and the numbers

The site and the men behind it, the two-week design, the race with Chrysler, 410 days of building, the mast, the empty years, the 1945 crash, King Kong, the lights and the numbers.

Architecture

How the Parthenon was built with such limited technology: nine years, 100,000 tons of marble, no mortar, and curves you cannot see

Pericles and the money, the architects, the quarry and the road, the cranes and the fitting, the invisible curves, the sculpture, the workers' wages, the explosion, the marbles and the restoration.

Architecture

Who built the Pantheon in Rome and how: Agrippa's name, Hadrian's building, the concrete dome that is still the largest, and 1,900 years of use

Agrippa and Hadrian, the unknown architect, the concrete dome and how it was poured, the oculus, the piers and arches, the Egyptian columns, the church, the Barberini bronze, Raphael, and visiting.

Architecture

How Roman aqueducts were built: surveying a slope of inches per mile, tunnels, siphons and arches, who did the work, and why the water still runs

The spring, the survey, the channel underground, tunnels and siphons, the arches and their centering, the mortar, the tanks, the workers, Rome's eleven aqueducts, and the ones still running.

Architecture

Chartres Cathedral facts and architecture: the fire of 1194, 26 years to rebuild, 176 windows of medieval glass, the labyrinth, the two spires and the relic that built it

The relic and the fire, the 26-year rebuilding, the High Gothic plan, the glass and its blue, the portals and sculpture, the labyrinth, the spires, the cult of carts, the cleaning, and visiting.

Architecture

Bauhaus architecture: what the style is, how to recognise it, the school that made it, and the buildings to know from Dessau to Tel Aviv

The school and its three cities, the ideas, how to recognise the style, the buildings from Dessau to Tel Aviv, the closure and the exile, Bauhaus vs Art Deco and modernism, and the myths.

Architecture

Art Deco buildings in New York City: the 25 to see, from the Chrysler Building to the Bronx, and a walking order

Why New York, the setback law, Midtown from Chrysler to Rockefeller Center, downtown from 70 Pine to One Wall Street, the Bronx and Brooklyn, the apartment towers, the lobbies, and a route.

Architecture

How the Panama Canal was built: the French failure, the mosquitoes, the Culebra Cut, the locks and Gatun Lake, ten years and 25,000 dead

De Lesseps and the French collapse, 1903 and Roosevelt, Gorgas and the mosquitoes, Stevens's railway, Goethals, the Culebra Cut, Gatun Dam and lake, the locks, the workers and the dead, 1914 and 2016.

Architecture

How the moai of Easter Island were built and moved: the quarry at Rano Raraku, the walking statues, the hats, the eyes, and why they were toppled

Rano Raraku and its 400 unfinished statues, carving in tuff, the buried bodies, the pukao and the eyes, walking the statues with ropes, the roads, the toppling, the collapse argument, and visiting.

Architecture

Nazca Lines: what they are, who made them and how, the theories from astronomy to aliens, and what the new AI survey found

The lines and figures, how they were scraped and why they survive, the Nazca people, the stake-and-cord method, the calendar, water and ritual theories, the runway myth, the 2024 AI discoveries, and how to see them.

Architecture

Who built the Kremlin in Moscow: the Italian architects of Ivan III, the red walls of 1485–95, the cathedrals, the towers and the stars, and what "Kremlin" means

The forts before it, Ivan III and his Italians, Fioravanti's cathedral, the walls and towers of 1485–95, the palaces and the bell tower, 1812, the Soviet century, the word, the numbers and visiting.

Architecture

What is a flying buttress? How it works, why Gothic cathedrals needed it, where to see the best ones, and what it is not

The thrust of a vault, the ordinary buttress, the flyer and the pinnacle, Notre-Dame, Chartres, Amiens and Beauvais, the physics, the parts, the best examples and the common mistakes.

Architecture

Why do old houses have two front doors, high ceilings, so many doors and low ceilings? The answers, room by room

Two front doors, high and low ceilings, doors everywhere, small closets, transoms, the bedroom sink, the door to nowhere, the milk door, the coal chute, the back stairs, and the myths about taxes and funerals.

Architecture

How Tower Bridge was built and why it is famous: the 1884 competition, the steel inside the stone, the bascules and the engines, the 1952 bus jump, and the London Bridge mix-up

The need, the competition, Jones and Barry, the piers and the steel, the Gothic cladding, the hydraulics, the walkways, 1894, the bus jump, the colours, and the London Bridge confusion.

Architecture

What is a gargoyle? What it does, what it symbolises, the difference from a grotesque, the legend of the dragon, and the best ones to see

The spout and the word, the monsters and the meanings, gargoyle vs grotesque vs chimera, the dragon of Rouen, the ancestors, the best to see, the Darth Vader, and the myths.

Architecture

Architecture terms explained: what a cupola, portico, pediment, cornice, colonnade, rotunda, facade, keystone and 20 other words mean, with the buildings that show them

Thirty words, one paragraph each: cupola, portico, pediment, cornice, colonnade, rotunda, facade, keystone, dome, vault, pilaster, entablature, frieze, arcade, loggia, nave, apse, clerestory, spire, dormer, quoin and more.

Architecture

What is a mansard roof? What it looks like, why Paris and Second Empire America are full of them, the tax story, the pros and cons, and how to spot one

The shape, Mansart and the Louvre, Haussmann's Paris and the height rule, Second Empire America, mansard vs gambrel vs hip, dormers and slate, the modern extension, the movies, pros and cons, and the myth.

Architecture

How were arches built, and who invented them? From Mesopotamian brick to the Roman arch, the Gothic point and the steel arch, with the centering that made them

False arches and true, Mesopotamia and Egypt, the Etruscans and Rome, centering, voussoirs and the keystone, why it stands, the shapes and their dates, vaults, domes and bridges, the great arches and the myths.

Architecture

How are domes built? From the Pantheon's concrete to Brunelleschi's bricks, the pendentives of Hagia Sophia, iron, geodesics and the stadium roof

The hoop stress, the Pantheon, pendentives, Brunelleschi without centering, drums, lanterns and chains, St Paul's three shells, the iron Capitol, concrete shells, geodesics and stadium roofs, and the records.

Architecture

How stained glass windows were made in medieval times: the glass, the colours, the lead, the paint and the firing, from Theophilus to Chartres

Theophilus's recipe, the furnace and the colours, blowing the sheets, the cartoon table, cutting and grozing, painting and firing, the lead cames, the armature, flashed red and silver stain, the workshops and the survival.

Architecture

How was concrete invented? From Nabataean cisterns and Roman pozzolana to Smeaton, Aspdin's Portland cement, Monier's flowerpots and the reinforced concrete of the 20th century

Lime and the Nabataeans, Roman pozzolana and why it heals, the lost recipe, Smeaton's lighthouse, Aspdin's patent, Monier's flowerpots, Hennebique, prestressing, the modern mix and its cracks, the myths.

Architecture

The oldest buildings in America: Taos Pueblo, the Palace of the Governors, St Augustine, the Fairbanks House and the oldest still in use, state by state

Taos and Acoma, Mesa Verde, the Palace of the Governors, St Augustine, the Fairbanks House, the oldest church, tavern, school and capitol, the oldest by state, and the myths.

Architecture

The oldest church in the world: Dura-Europos, Aqaba, Megiddo, Etchmiadzin, the Nativity, and the oldest still in use, by claim and by evidence

Dura-Europos, Megiddo and Aqaba, Etchmiadzin, the Nativity and the Holy Sepulchre, Rome's oldest, Trier, Ethiopia, Georgia, the oldest still in use, the oldest in Britain and America, and the disputes.

Architecture

The oldest castle in the world and the biggest: Aleppo, Doué-la-Fontaine, the Tower of London, Windsor, Prague, Malbork and the ones still lived in

Aleppo, Doué and the motte, Langeais and the White Tower, Windsor and the Tower as homes, Malbork, Prague and Windsor as the biggest, the largest by country, and the arguments.

Architecture

The oldest cities in the world still inhabited: Jericho, Damascus, Aleppo, Byblos, Athens, Varanasi, Plovdiv and the rest, with what "oldest" means

Jericho, Byblos, Damascus and Aleppo, Susa and Sidon, Athens and Argos, Plovdiv, Varanasi, Luoyang, Jerusalem, Erbil, the ruined oldest, the Americas, and how the dates are argued.

Architecture

The largest churches in the world: St Peter's, Yamoussoukro, Aparecida, Seville, Milan, St John the Divine, and the tallest, longest and widest

St Peter's and its rivals, the top ten by area, the largest Gothic, Anglican, American and Orthodox churches, the tallest towers, the longest naves, the biggest domes, the largest by seats, and the measurement fights.

Architecture

Famous architects and their works: 30 names from Imhotep to Zaha Hadid, what each built and why it mattered

From Imhotep's Step Pyramid to Hadid's curves: thirty architects, the building to know for each, the idea behind it, and where it is.

Architecture

Washington Monument facts and history: why the colour changes a third of the way up, the 36-year pause, the pope's stone, the aluminium tip and the numbers

Mills's design, the 1848 cornerstone, the stolen stone and the stump, Casey and the 1884 finish, the colour line, the aluminium tip, the stones inside, the records, the earthquake and the myths.

Architecture

How the Lincoln Memorial was built: the swamp, the fight over the site, Bacon's temple, French's statue in 28 blocks, and the 1922 dedication

The fifty-year delay, the swamp and the site fight, the foundations, Bacon's temple, French's statue and the Piccirillis, the inscriptions, 1922, Anderson and King, the reflecting pool, the numbers and the myths.

Architecture

How the Sydney Opera House was built: Utzon's sketch, the shells nobody could build, the orange that solved them, the resignation, and 14 years and 14 times the budget

The competition and Saarinen, the shells and the sphere, Arup's ribs, the podium blown up, the tiles, the politics and the resignation, Hall's interiors, the 1973 opening, the lottery, the numbers and the myths.

Architecture

How the Burj Khalifa was built on sand and so fast: the 192 piles, the buttressed core, the concrete pumped 600 metres, the spire and the 2009 bailout that gave it its name

The design and the buttressed core, the piles and the raft, the sand question, the wind and the Y, the concrete and the night pours, the spire, the cladding, the workers, the 2009 crisis and the name, the numbers and the myths.

Architecture

Hearst Castle history: William Randolph Hearst, Julia Morgan, 28 years of building, the zoo, the pools, the guests, Citizen Kane and the state park

The ranch, Hearst and Morgan, the 1919 letter, the Casa Grande and the guest houses, the pools, the collections, the zoo, the guests, the money troubles, Citizen Kane, the state park and the myths.

Architecture

Biltmore Estate history: George Vanderbilt's 250-room French château in North Carolina, Hunt and Olmsted, the 1895 opening, the forest that began American forestry, and the family that still owns it

Vanderbilt and the land, Hunt's château, Olmsted's gardens and the forestry school, 1895, Edith and the forest sale, opening in 1930, the war, the winery, the Cecils, the numbers and the myths.

Architecture

How lighthouses were built in the 1800s and in the open ocean: Eddystone, Bell Rock, Minot's Ledge, the screw-pile, the caisson, the Fresnel lens and the keepers

Eddystone and the dovetailed stone, Bell Rock in the tides, Minot's Ledge, brick towers on sand, screw-piles, caissons, the Fresnel lens, the keepers and the end of them.

Architecture

How the Tower of London was built: William's White Tower of 1078, the stone from Caen, the walls of Henry III and Edward I, the moat, and 950 years of fortress, palace, prison and zoo

1066 and the Roman corner, the White Tower and its builders, Henry III's inner wall, Edward I's outer wall and moat, the palace and the menagerie, the prison, the Jewels, the ravens and the numbers.

Architecture

How Versailles was built: the hunting lodge, Louis XIV's four campaigns, 36,000 workers, the water that never sufficed, the Hall of Mirrors, and how long it really took

The lodge, Vaux and the decision, Le Vau's Envelope, Hardouin-Mansart's wings and the Hall of Mirrors, the gardens and the canal, the water and the Marly machine, the workers, the court, the chapel, the cost and the myths.

Architecture

Neuschwanstein Castle history: Ludwig II, Wagner, the theatre designer who drew it, 17 years of building, the king's death in the lake, the Nazis' loot and the Disney castle

Ludwig and Wagner, Jank's stage design, the modern building inside the medieval one, the Throne Hall and the Singers' Hall, 172 days, 1886, the tourists, the Nazi depot, Disney, and the myths.

Architecture

Windsor Castle and Edinburgh Castle history: two royal fortresses in timelines, from William the Conqueror and Malcolm III to the fire of 1992 and the Stone of Destiny

Windsor: the motte, Edward III, the Garter, St George's, Wyatville, the fire; Edinburgh: the rock, St Margaret's Chapel, 1314, the Lang Siege, Mons Meg, the Honours, the Gun and the Tattoo; and the myths.

Architecture

What is a Craftsman house? The low roof, the porch, the tapered columns, the built-ins, where it came from and how to tell it from a bungalow, a Prairie house and a ranch

The Arts and Crafts roots, Stickley and the Greenes, the features to look for, the bungalow and the kit house, Craftsman vs bungalow vs Prairie vs Tudor vs ranch, where to see them, prices, and the myths.

Architecture

What is a Tudor style house? The half-timbering, the steep roofs, the tall chimneys, the real Tudor of 1500 and the American Tudor Revival of 1920, and how to tell them apart

The real Tudor of 1500, the timber frame and the jetty, the revival of 1890–1940, Stockbroker Tudor, the features, Tudor vs Cotswold vs Craftsman, where to see them, prices and problems, and the myths.

Architecture

What is a Cape Cod house? The 1690 original, the steep roof and central chimney, the half, three-quarter and full Cape, the Royal Barry Wills revival and the Levittown Cape

The original of 1690–1850, the roof and the chimney, half, three-quarter and full Cape, Wills and the 1930s revival, Levittown, the features, Cape vs Colonial vs saltbox vs ranch, where to see them, and the myths.

Architecture

What is a bungalow? From Bengal to Pasadena and Chicago: the one-storey house with a porch, the Craftsman, California and Chicago bungalows, and what the word means in Britain, India and Australia

Bengal and the British veranda, the English seaside, California and the Craftsman, Chicago brick, the bungalow court and the kit, Australia and India, the features, bungalow vs cottage vs Cape vs ranch, where to see them, and the myths.

Architecture

What is a brownstone? The stone, the stoop, the row house of New York and Brooklyn, why it crumbles, the parlor floor and the garden level, and how it became the most wanted house in the city

The stone and the quarries, the row house plan, the stoop, the floors and their names, Italianate and neo-Grec fronts, the flaking and the patching, the decline and the revival, prices, and the myths.

Architecture

What is a saltbox house? The long back roof, the lean-to that made it, the central chimney, the 1650–1750 originals of New England, the Newfoundland saltbox and the tax myth

The shape and the name, the lean-to that made it, the chimney and the plan, the originals of 1650–1750, Newfoundland's saltboxes, the revival and the modern one, saltbox vs Cape vs Colonial, and the tax myth.

Architecture

What is a shotgun house? The one-room-wide house of New Orleans, its Haitian and African roots, the rooms in a row, the double and camelback, and why the name

The shape and the plan, the New Orleans and Haitian origins, the Yoruba house, the name, double shotgun and camelback, the porch and the brackets, the shotgun cities, Elvis and Katrina, and the myths.

Architecture

What is a ranch style house? Cliff May's California ranch, the low roof and the picture window, the 1950s suburb, the raised ranch and the split, and why it is coming back

Cliff May and the rancho, the features, the plan and the family room, the kinds, raised, split and storybook, why the suburbs built it, Lakewood and Levittown, the fall and the return, ranch vs bungalow vs mid-century, prices, and the myths.

Stamps

How to tell whether a Soviet stamp is valuable

Print run, perforation, varieties, cancellation and condition – the five signs that separate an ordinary issue from a scarce one.

Badges

Soviet badges: how to sort a collection by theme

Seven themes, dating clues and the layout of an archive of 3,332 badges from 1917 to 1991.

Coins

How to tell whether a Soviet coin is valuable

Year, die variety, mintage and condition – the four signs that separate a scarce coin from an ordinary one.

Banknotes

Soviet banknotes: the issues explained

The 1922–1924, 1947 and 1961 reforms and the final 1991 notes – the lines that split all Soviet paper money.

Postcards

Soviet postcards: how to date one from the back

Imprint data, publisher, price, postmark and stamp – five clues that give away the year.

Labels

Soviet matchbox labels: what phillumenists collect

Series, themes and scarcity in the smallest posters of the Soviet era.

Posters

Soviet posters: dating a sheet by its graphics

Lettering, composition, inks and photomontage – how a sheet gives away its decade.

Stamps

Soviet space stamps: an overview

181 issues from 1950 to 1991: how the theme ran year by year and what collectors look for.

Stamps

Soviet stamps with Lenin: telling the issues apart

183 issues from 1920 to 1991: catalogue number, face value, perforation, paper and overprints.

Badges

Soviet space badges: a guide to the issues

Five waves of issues from the first satellite to international crews, two traps in the theme and what the archive holds.

Badges

Soviet city badges: how to build a geographic series

Coats of arms, routes, jubilees and hero cities – five types of city badge and how to complete a series.

Coins

Soviet commemorative coins year by year

54 types of commemorative rouble from 1965 to 1991, five issue periods and what makes one coin scarcer than another.

Calendars

Soviet pocket calendars: collecting graphics that fit a wallet

The one collectible that dates itself: what is collected besides the year, and why pre-war calendars look strange.

Stamps

Imperforate Soviet stamps: telling them from trimmed ones

An imperforate stamp and a trimmed one look alike – margins, size and the paper edge tell them apart.

Postcards

Soviet holiday postcards: what people collect

Four holiday occasions, artist series and why New Year cards are collected more than any other.

Badges

Soviet military badges: award, unit sign and souvenir

An issued award, a unit sign and an anniversary souvenir – three different things that get mixed up.

Badges

Soviet sport badges: fitness, ranks and spartakiads

Fitness, ranks, spartakiad series by discipline and the 1980 Olympics – four lines with a clear finish.

Coins

Soviet coins 1961–1991: the series and its die varieties

Nine denominations in one series, two alloys and die varieties – how to read the most common collection of all.

Banknotes

Soviet banknotes of 1961: denominations and signs

Seven denominations, two groups of notes and two watermarks – what to check against the light.

Posters

Soviet posters on labour and war: two main themes

Labour speaks in figures and plans, war with a face and an order: the language of two poster themes.

Badges

Lenin badges: what is actually in the box

Leningrad, named-after works, organisation insignia and portraits – four groups that keep getting confused.

Coins

Soviet silver coins: three separate eras

Circulating silver of the 1920s, the Olympic series and commemorative three roubles – three unlike eras.

Banknotes

Soviet banknotes of 1991: the last issue

Nine denominations of the last Soviet issue, the new 200, 500 and 1000 roubles and a different watermark.

Coins

Wheat pennies: which 1909–1958 cents are worth keeping

Date, mint mark, condition – the three things that decide whether a wheat cent is more than a cent.

Coins

Silver quarters and dimes: how to spot 90% silver

Date, edge, weight – three checks that find the silver in a jar of change in seconds.

Stamps

The Inverted Jenny and the other American inverts

One sheet of 100 escaped in 1918. What made it possible – and how to tell a real error from a made one.

Guides

An inherited shoebox of stamps: what to do first

Do not soak, do not peel, do not throw the envelopes away. What to actually do with an inherited box.