Leonardo da Vinci (1452 - 1519), painter, sculptor, architect and engineer, kept notes and drawings of his studies, ideas and inventions. Over 7,000 pages have survived, including this notebook known as Codex Arundel after its English collector Thomas Howard, 14th earl of Arundel.
The structure of the notebook reveals that it was not originally a bound volume. It was put together after Leonardo's death from loose papers of various types and sizes, some indicating Leonardo's habit of carrying smaller bundles of notes to document observations outdoors.
Many of the pages were written in 1508; others come from different periods in Leonardo's life, covering practically the whole of his career. The notebook features many topics, including mechanics, the flow of rivers, astronomy, optics, architecture and the flight of birds, demonstrating Leonardo's intense curiosity.
The manuscript is written in Italian, in Leonardo's characteristic 'mirror writing', left-handed and moving from right to left.
Leonardo comes up with a solution that consists of two tubes, one for inhaling and the other for exhaling. In order to protect the upper parts of the tubes from the waves, he devises a float, and then he explains that the tubes are built in such a way that they do not break. The strategy Leonardo adopts is to make the tubes flexible by articulating them at intervals, and by having wires in these articulations.
Then, Leonardo advises that a sack should be placed below the chin of the apparatus to collect waste; the sack could be emptied without compromising the functioning of the apparatus. Particularly significant here is the way Leonardo details the structure of his apparatus by making use of 'transparent' and 'exploded' views, which are graphic techniques that he explored extensively in his studies of human anatomy.
In addition to a fascination with the abstract geometry of the patterns of reflection, Leonardo was also interested in the potential utility of concave mirrors as sources of heat. On the right-hand page Leonardo argues that in concave mirrors of equal diameter, the one which has a shallower curve will concentrate the highest number of reflected rays on to a focal point, and 'as a consequence, it will kindle a fire with greater rapidity and force'.
Leonardo’s drawings show his attempts to develop a mechanical understanding of sound. The main sketches on the folio on the right relate to the design of a mechanical organ to play a canon in four parts. This consists of an outer wheel with pipes to serve as mechanical voices and a wheel in the middle with four cogs to each take the part of a singer.
See more of Leonardo notebook on Turning the Pages™.