Engineering: quotes, facts and reflections - Page 3

In this room

Follow the subject sideways.

Cards are connected by subject and by mood. Move through the complete sequence below, or cross into a neighbouring part of the archive.

40Drive

15Stillness

57Wonder

Q1970

WonderScience

The Great Trigonometrical Survey used baselines and triangulation across India, producing geodetic measurements that identified Peak XV as the world's highest known summit.

Beginning in 1802, survey teams carried precision instruments through heat, monsoon and mountain terrain. Peak XV was observed from distant stations on the northern plains, then its height was corrected for Earth's curvature, atmospheric refraction and the instruments themselves. The calculations identified the highest known summit without an ascent. The same survey also served the East India Company's colonial administration, turning terrain into both knowledge and control.

Great Trigonometrical SurveyRead card

Q1987

DriveBiography

Mary Jackson petitioned the City of Hampton to attend graduate courses held at a segregated white school, then became NASA's first Black woman engineer in 1958.

Jackson entered Langley's segregated West Area Computing unit in 1951, then moved into experiments in a supersonic pressure tunnel. Her training route required after-hours mathematics and physics classes in a school she was legally barred from attending without special approval. She went on to publish research on airflow and boundary layers at supersonic speeds. Later, she accepted a lower grade to manage equal-opportunity programmes, trading personal rank for the power to widen other people's routes upward.

Mary JacksonRead card

Q1988

DriveBiography

Christine Darden developed computer models for predicting and reducing sonic booms, helping engineers reshape supersonic aircraft to soften their acoustic impact.

Darden arrived at NASA Langley in 1967 as a human computer, one of the last generation hired to perform calculations for engineers. Six years later she moved into aerospace engineering and wrote code to model the shock waves that gather into a sonic boom. Her work helped show that noise on the ground could be influenced by an aircraft's geometry rather than accepted as the fixed price of speed. She eventually led the sonic-boom group: the person once assigned the arithmetic came to shape the research question.

Christine DardenRead card

Q1989

DriveBiography

Annie Easley moved from hand calculation to programming, developing and testing code for energy systems, battery research and NASA's Centaur upper-stage rocket.

Easley joined the aircraft engine laboratory in Cleveland in 1955 as one of only four Black employees, calculating research problems by hand. As electronic computers took over, she learned FORTRAN and SOAP rather than letting automation define the edge of her career. Her code supported studies of alternative power and the liquid-hydrogen Centaur stage that sent spacecraft toward the Moon and planets. Adaptability here was not a slogan; it was a new syntax learned while the workplace itself was changing.

Annie EasleyRead card

Q1991

WonderBiography

Radia Perlman's spanning-tree algorithm lets network bridges agree on a loop-free path, blocking redundant links until a failure makes one useful again.

Redundant connections make a network resilient, but unmanaged loops can make frames circulate and multiply until communication collapses. Perlman's 1980s algorithm lets distributed switches elect a logical tree, temporarily quieting selected links while preserving them as alternative routes. If the topology changes, the tree can be calculated again. The elegance is institutional as much as mathematical: no central traffic officer is required, yet independent machines arrive at one workable map.

Radia PerlmanRead card

Q2002

WonderScience

A scanning tunnelling microscope maps a conducting surface by holding an atom-sharp tip extremely close and measuring the quantum current that tunnels across the gap.

Classically, electrons in the sample and tip should remain separated by the vacuum barrier. Quantum mechanics gives their wave-like probability a small reach beyond it, creating a tunnelling current that changes steeply with distance. As feedback raises and lowers the tip to keep that current steady, the motion becomes a map of the surface's electronic topography. Gerd Binnig and Heinrich Rohrer turned this effect into an instrument at IBM Zurich, earning a share of the 1986 Physics Nobel Prize. Near enough, a forbidden crossing becomes a ruler.

Scanning tunnelling microscopeRead card

Q2003

WonderScience

An atomic force microscope follows a surface with a tip on a tiny cantilever, translating minute forces and deflections into a three-dimensional nanoscale map.

Scanning tunnelling microscopy depended on an electrical current and therefore favoured conducting samples. In 1986 Gerd Binnig, Calvin Quate and Christoph Gerber proposed a different messenger: force. Their microscopic tip can touch a surface or hover just above it while attraction and repulsion bend the cantilever; a laser commonly magnifies that motion for the detector. Because the method can work on insulators and in liquids as well as in vacuum, it brought polymers, membranes and biological structures into the nanoscale landscape. Seeing became a disciplined form of touch.

Atomic force microscopyRead card

Q2004

WonderScience

Electron microscopes use short-wavelength electron beams and electromagnetic lenses to resolve structures far smaller than visible-light microscopy can distinguish.

A light microscope loses resolving power when the details approach the wavelength of its illumination. Electrons also behave as waves, but accelerated electrons can have much shorter wavelengths. Ernst Ruska and Max Knoll used magnetic coils to focus them; their 1931 prototype led to Ruska's 1933 instrument that surpassed optical resolution. Modern transmission instruments send electrons through very thin specimens, while scanning designs read signals from surfaces. The images require vacuum, preparation and interpretation, yet they opened cells, viruses and materials far beyond the frontier of glass lenses.

Electron microscopeRead card

Q2008

WonderScience

Photogrammetry finds matching points in overlapping photographs and uses camera geometry and parallax to calculate distance, shape and three-dimensional coordinates.

A feature shifts within an image when the camera moves; that apparent disagreement carries geometric information. With known or recoverable camera positions, software traces corresponding points through several views and triangulates where they sit in space. The result may be a map, a building survey, a terrain model or a record of an object too fragile to touch. Here the camera is a measuring instrument disguised as an image-maker.

PhotogrammetryRead card

Q2012

WonderScience

A Kibble balance realizes the kilogram by balancing weight against electromagnetic force measured with quantum electrical standards tied to the fixed value of Planck's constant.

The balance works in two linked modes. One matches a mass's weight with magnetic force on a current-carrying coil; the other moves the coil to calibrate the same system through induced voltage. Quantum standards make the electrical measurements traceable to Planck's constant, whose value was fixed in the 2019 SI. A suitably equipped metrology institute can now realize mass from a reproducible recipe instead of comparing everything to one ageing object.

Kibble balanceRead card