`That Mars is inhabited by beings of some sort, we may consider to be as certain as it is uncertain what those beings may be," wrote Percival Lowell in 1906. He was sharing, not just a personal conviction, but also a view that had been widely held for generations. Indeed, throughout the 19th century the real question was not so much whether there was intelligent life on Mars, but rather how we could communicate with it.
There were lots of bright ideas. Karl-Friedrich Gauss, one of the great mathematicians of that century, suggested planting pine trees in large geometric patterns in Siberia. The Austrian astronomer, Carl von Littrow, on the other hand, favoured fire-filled ditches in the Sahara desert. And the French inventor Charles Gros was even more adventurous: he proposed building a concave mirror with a very long focal length to concentrate the sun's rays on to the Martian deserts.
The rays would scorch the Martian surface in the same way as we can burn a piece of paper with a magnifying glass, and he went on to describe how a judicious swinging of the mirror would make it possible to write a message on the Martian sands.
Percival Lowell was born in Boston 145 years ago today, on March 13th, 1855. He devoted his energies to building the Lowell Observatory at Flagstaff, Arizona, where the air - or so he had been told - was the most "stable" in North America.
When, in 1877, an Italian astronomer called Giovanni Schiaparelli detected a strange network of straight lines on Mars, which he called canali, the Italian for channels, Lowell looked at them from Flagstaff, and proceeded to build an entire new world around them.
The channels, he proclaimed, were irrigation canals. They had been dug by an intelligent race of Martians to transport water from the melting polar ice-caps to the more habitable and amenable lower latitudes of the planet.
The visible lines, moreover, were not the actual water courses, but the results of irrigation and cultivation on either side, and where the lines crossed there were great cities.
"A mind of no mean order," Lowell wrote, "would seem to have presided over the system - a mind of considerably more comprehensiveness than that which presides over the various departments of our own public works. Party politics, at all events, have had no part in them, for the system is planetwide and hints at beings who are in advance of us."
But time, better telescopes and, conclusively, the Mariner space missions of the 1950s, laid Percival Lowell's Martian ghosts to rest.