The British Library has digitized 570 loose pages of notes written and drawn by Leonard da Vinci to compile a notebook which is called, The Codex Arundel . You can view the document online for free, although it’s written in Italian and uses his “characteristic left-handed mirror-writing (reading from right to left).” The Guardian suggests enjoying the work of the self-taught Renaissance man as it is, without translation: The digitised British Library manuscript is a fascinating artefact in itself, just to browse.
Kaynak: A big chunk of Leonardo da Vinci’s notebooks have been digitized and can be viewed online