Questions from natural clouds
Wilson studied in Manchester before moving to Sidney Sussex College, Cambridge. Observations of optical effects in clouds on Ben Nevis in 1894 prompted him to reproduce such conditions in the laboratory and investigate condensation around ions in air.
References: [1]
Making tracks visible
In an expansion cloud chamber, moist gas expands and cools. Vapour condenses around ions along the path of an ionizing particle, leaving a line of droplets that can be seen and photographed. The visible record is the condensation trail.
In 1911 Wilson photographed individual particle tracks, including those of alpha and beta particles. Later investigators improved the instrument and used it to study scattering, nuclear transformations and new particles.
Physics and atmospheric electricity
Wilson shared the 1927 Nobel Prize with Arthur Compton. He continued investigating atmospheric electricity, including thunderstorms, well into retirement. His career connected particle detection in the laboratory with the physics of clouds and electricity in nature.