Compound Pulley systems were of special interest to Leonardo Da Vinci. This was highlighted by the many sketches of Pulleys that was found in the Codex, and an example of a sketch is given in the picture. The sketch shows a simple pulley system hoist, which is a system that lifts or lowers a weight with the lesser amount of effort with an increase of pulleys present in the system. Moreover, he tried to associate various numbers to the various elements of the system to understand the concept of physics better.

Sources:-

LEONARDO3 - Leonardo da Vinci | MACHINES COLLECTON - COLLEZIONE DELLE MACCHINE, www.leonardo3.net/leonardo/semplici_eng.php.

Image Courtesy:- Wikimedia Commons , private domain

https://commons.wikimedia.org/wiki/File:20Pulley-Da_Vinci.JPG