"A spendthrift in invention;" versatility and daring.

The screw-propeller

vs

. the paddle-wheel for marine propulsion.

Designs and constructs the steam-frigate "Princeton" and the hot-air ship "Ericsson".

The Civil War and his services in the art of naval construction.

His new model of a floating battery and warship, "The Monitor".

The battle between it and the "Merrimac" a turning-point in naval aspect of the war.

"The Destroyer," built in connection with Mr. Delamater.

Improves the character and reduces friction in the use of heavy ordnance.