Drawings of a Mad Man/Genius-John Ericsson's Monitor Concept

Ericsson first drew a traverse sketch of his idea and then drew over it with a long view. As one can see Ericsson "showed his work" by working out the math on top of the drawings.

While these look like sketches drawn by a mad man at 3 in the morning who had not been to bed in over 72 hours, these are actually inventor/designer/engineer John Ericsson's 1854 concept of a "monitor" type warship. After much political stalling, the Ironclad Board would formally endorse his design in 1861. The idea behind Monitor, however, had been shuffling around in Ericsson's head long before the outbreak of war.

A rough idea of his monitor's submerged propeller system.

According to a 1911 biography The Life Of John Ericsson, the Swedish-born engineer had the idea from early on  in his professional career.  Monitor, according to Ericsson, was not just a class warship, but rather a fundamental shift in the way architects should look at warship design.  He wrote "The monitor of 1854 was the visible part of my system, and its grand features were excluded from its published drawings and description...An impregnable and partially submerged instrument for destroying ships of war has been one of the hobbies of my life. I had the plan matured long before I left England. As for protecting war engines for naval purposes with iron, the idea is as old as my recollection."

Ericsson's "monitor system" not only was about designing ships with armored turrets, but also building them with a submerged screw propeller that was safe from hostile fire. In Ericsson's mind, the water surrounding a ship was just as important as any metallic armor protecting the exposed area.