After seeing the first outdoor pumping area, you gather your munitions and head up the stairs. There's a room to the left, and a stone spiral staircase ahead of you. Enter the room to the left. Although the window is large enough for the player to go through - there isn't a machine gun available to do so (yet). If the player "does" get through the window - now or later - there's a hidden door that re-accesses the stairwell. There is nothing down there but a few fighters, and a Moses statue.
Continuing up the stone spiral staircase, you enter a hallway with a switch and the lone terminal. There is a secret door on the same wall as the terminal - between the entry and the term - nestled between the candlesticks. Inside is some extra ammo, a 1x powerup, and an SMG that cannot be retrieved.
After activating the switch across from the terminal, continue towards the save terminal near the start of the level. The oval hallway has a newly revealed upward staircase - "take out" the oncoming fighters, and watch your back for the outdoor drones. Continue down the hallway (past the second outdoor jugg), grab the machine gun and ammo - remove the trooper and fighter - proceed through the door they were guarding - this is the first accessible outdoor area.
The outdoor areas (with the exception this one, and the hedge maze) are inaccessible....if you could get out there, you'd crash.
Enter the structure in the North East area of the map. The manuscript is located in the room at the end of the upstairs hallway - also inside is a 1x powerup. Ammo can be found underneath the hallway. The area in the far East (2 outdoor buildings), guarded by the cyborg is inaccessible.
After retrieving the manuscript - head back towards the start of the level. You can either go back down the spiral staircase towards the oval hallway, or drop down through the newly revealed opening - on the wall opposite the stairwell.
Once again the player can use the save term (each phase of the level ends at the same save term - so the entire level only has one) - or go out through the big wooden door (re-entry is impossible). Once in the second outdoor area, the payer must search for the exit teleporter. It's located in the far South West area of the map - behind the sinking tree.
(Level name taken from a chapter in the book "Discovering the life of: Leonardo da Vinci" by Serge Bramly - the book that inspired the scenario's creation)