Even Einstein was fan of this influential physicist

GREAT SCOTTISH SCIENTISTS

Number 7 JAMES CLERK MAXWELL

JAMES Clerk Maxwell was one of the greatest theoretical physicists the world has known and is regarded as the 19th-century scientist who most influenced 20th-century physics.

Maxwell's work on electromagnetism and light paved the way for luminaries such as Max Planck and Albert Einstein, and in 1931, the centenary of Maxwell's birth, Einstein described the Scot's work as the "most profound and the most fruitful that physics has experienced since the time of Newton".

Despite his reputation within the scientific community, the Edinburgh-born Maxwell has never attracted the kind of popular profile associated with other Scottish scientific pioneers such as Bell or Fleming. Yet, he is commemorated by a mountain range on Venus, Maxwell Montes, and by the James Clerk Maxwell Telescope on Mauna Kea, Hawaii.

A descendent of the notably creative Clerks of Penicuik, Maxwell was born in 1831. Initially privately tutored at his parents' estate at Glenlair, near Dumfries, he went on to attend Edinburgh Academy (where he was known as "Dafty"), then entered Edinburgh University at the youthful age of 16, having already written a scientific paper on how to draw a perfect ellipse using pins and string.

He went on to Trinity College, Cambridge, later becoming a fellow, and in 1856 was appointed Professor of Natural Philosophy at Aberdeen's Marischal College (marrying the university principal's daughter, Katherine Dewar). He took a similar post at King's College London in 1860.

Maxwell revolutionised our understanding of electromagnetics with his elegantly concise "Maxwell's equations", as they became known, showing that electric and magnetic fields travel through space in waves, at a constant velocity.

His mathematical examination of Michael Faraday's theory of electrical and magnetic forces provided the first conclusive evidence that light consisted of electromagnetic waves.

He also played an important part in establishing the kinetic theory of gases, established the nature of Saturn's rings in 1857, investigated colour perception and colour blindness, and made an early venture into colour photography, using a length of tartan ribbon.

His formidable scientific mind also enjoyed a prolific output of pawky Scots verse, including a theoretical physicist's take on a famous Burns song: "Gin a body meet a body/Flyin' through the air/Gin a body hit a body/Will it fly? and where?"

After a spell of "retirement" at Glenlair, Maxwell returned to Cambridge in 1871 to establish a physics laboratory as the first Cavendish Professor of Experimental Physics. He died of cancer there in 1879, aged only 48.

On the 21st of this month, when the Planetary Society launches Cosmos I, the first solar sail spacecraft, the mission will test the concept that spacecraft can harness the pressure of light particles (photons) from the sun. The existence of that pressure was demonstrated in theory by Maxwell as far back as 1873.