In 1961, Cuba sent volunteers to teach a million adults to read
Many of the volunteers were teenagers who lived with rural families. By the end of 1961, about 75% of the million adults had basic literacy.
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Museums scan mummies to read them without unwrapping
CT scanners let researchers see inside a wrapped mummy in cross-section, revealing bones, teeth, amulets and embalming tools without cutting the wrappings.
A census counts everyone on one day, then checks who it missed
A census counts every resident against one fixed date, then a separate survey checks how many the count still missed, and where.
A combi boiler heats water only when a tap opens
A combi boiler connects to the mains and heats water the moment a tap opens, with no cylinder to fill, top up or wait to reheat.
Ford's moving line cut Model T assembly to about 90 minutes
Ford cut assembly from twelve and a half hours to about 90 minutes in 1913. One car design, identical parts and 84 single-step jobs made it possible.
Sequoyah's Cherokee syllabary took hold within a few years
Sequoyah built the Cherokee syllabary from the language's own syllables. The Cherokee Nation adopted it in 1825, and literacy reportedly rose fast.
Smart thermostats learn your routine from your own adjustments
A smart thermostat learns a routine by copying the adjustments a household makes. The Heating Hub's Jo Alsop says geofencing drove Tado's 28% saving claim.
Adam's Bridge: a sunken shoal chain between India and Sri Lanka
Adam's Bridge is a 29 km chain of shoals between India and Sri Lanka, almost all underwater, that NASA says people could cross on foot until the 15th century.
El Niño strength comes down to Pacific sea temperature
An El Niño is judged by how far the Pacific warms above normal. NOAA and NASA track it with buoys, floats and satellites, and 0.5C marks the start.
Phonics teaches children to read by blending letter sounds
A phonics programme teaches a child to match letters to sounds, then blend those sounds together, starting with the letters used most often.
Tree rings date a drought to the exact year
A tree lays down one ring a year, wide when the season is wet and narrow when it is dry. Matched across many trees, those rings date droughts to the year.
Is Taco Bell safe to eat after the US Cyclospora outbreak?
Taco Bell pulled the lettuce tied to a US Cyclospora outbreak in July. Food safety scientist Tamika D. Sims says there is no reason to avoid the chain now.
Africa's crust has thinned to 13km at the Turkana Rift
Columbia geologists found crust at a stage called necking under Kenya and Ethiopia. They suggest the Indian Ocean could follow in a few million years.
How lost-wax casting turns a wax copy into a bronze sculpture
Wax is buried in a mould, melted out and replaced with molten bronze. The method runs from Benin's royal casters to Leonardo's unfinished horse.
Sweden raised the Vasa warship after 333 years underwater
Engineer Anders Franzén found the wreck in 1956. Cold Baltic water had left an estimated 95% of the wood, so divers could lift the hull in 1961.
The Dewey system shelves books by subject number, then letters
Melvil Dewey published the scheme in 1876. Ten classes of a hundred numbers sort a book by subject, and author letters settle ties on the shelf.
The 1871 act that ended religious tests at Oxford and Cambridge
The Universities Tests Act of 1871 ended Oxford's religious tests, in place since 1581, and opened Oxford, Cambridge and Durham to all faiths.
A chaplain's student hostel gave the Sorbonne its name
Robert de Sorbonne, a royal chaplain, opened a hostel for Paris students in 1257. Officially, the Sorbonne stopped being a university in 1970.
The Pantheon's dome has lasted nearly 1,900 years without rebar
Rome's Pantheon has stood almost 1,900 years with no rebar, largely left alone. Graded concrete, a hollow crown and a self-sealing mix explain why.
The African Union depends on outsiders to pay for peacekeeping
The African Union and its partners run ten peace operations. A UN official said in 2009 that their funding rests on the UN or a small pool of donors.
A 1927 IBM gadget solved Nuremberg's language problem
A system used at a 1927 labour conference ended up carrying Nuremberg's war-crimes trial live, in four languages at once.
A 1978 US law put Native American families first in adoption
The Indian Child Welfare Act told US states to place a Native child with family or their tribe first. The Supreme Court upheld it in 2023.
Al-Azhar: how a Fatimid mosque became a university
Al-Azhar began as a Fatimid mosque in 970. By 988 the state paid 35 scholars to teach there, and it later became a modern university in Cairo.
Alden Global Capital bought US newspapers, then stripped them
Alden Global Capital cut staff and sold real estate at the US papers it bought. A federal inquiry found it probably moved pension money into its own funds.