Liais, Emmanuel (1826–1900)
French astronomer who spent much of his life in Brazil, as Director of the
observatory of Rio de Janeiro. In 1860, he suggested that the dark regions
on Mars, instead of being oceans and seas,
as was widely believed at the time, might be tracts of vegetation (see Mars,
vegetation on). The summer melt-water from the poles, he believed, was
irrigating the soil at lower latitudes and causing the dormant plant life
there to rejuvenate and spread.