Swiss etcher, lithographer, draftsman and cartographer. He came from a humble family living in Zurich, his father was a baker. Art the age of eight, he had an accident resulting in a complicated broken femur which forced him to a long bed rest. Later, he had to go on crutches for several years. During his long convalescence Keller began to copy maps. Later he drew landscapes. After 1797 he was an apprentice to the painter and art dealer Henry Fuseli in Zurich and worked there until 1815. In 1799 he had drawn a map for a guidebook, later followed by similar works. In 1827 he published a map of the Canton of Zurich, in 1830 a wall map of Switzerland. After separating from Fuseli he established his own publishing house in Zurich. He drew maps of Swiss towns, and produced the first Swiss school maps (1823), school wall maps (1830) and school atlas (1842). //