Leonardo da Vinci was educated in his father's house receiving the usual elementary education of reading, writing and arithmetic. In 1467 he became an apprentice learningpainting, sculpture and acquiring technical and mechanical skills. He was accepted into the painters' guild in Florence in 1472 but he continued to work as an apprentice until 1477. From that time he workedfor himself in Florence as a painter. Already during this time he sketched pumps, military weapons and other machines.
Between 1482 and 1499 Leonardo was in the service of the Duke of Milan. He wasdescribed in a list of the Duke's staff as a painter and engineer of the duke. As well as completing six paintings during his time in the Duke's service he also advised on architecture, fortificationsand military matters. He was also considered as a hydraulic and mechanical engineer.
During his time in Milan, Leonardo became interested in geometry. He read Leon Battista Alberti's books onarchitecture and Piero della Francesca's On Perspective in Painting. He illustrated Pacioli's Divina proportione and he continued to work with Pacioli and is reported to have neglected his painting becausehe became so engrossed in geometry.
Leonardo studied Euclid and Pacioli's Suma and began his own geometry research, sometimes giving mechanical solutions. He gave several methods of squaring thecircle, again using mechanical methods. He wrote a book, around this time, on the elementary theory of mechanics which appeared in Milan around 1498.
Leonardo certainly realised the possibility ofconstructing a telescope and in Codex Atlanticus written in 1490 he talks of
... making glasses to see the Moon enlarged.
In a later work, Codex Arundul written about 1513, he says that
... inorder to observe the nature of the planets, open the roof and bring the image of a single planet onto the base of a concave mirror. The image of the planet reflected by the base will show the surface of...