On October 4, 1861, President Abraham Lincoln attended a demonstration of how hot air balloons might be used to gather military intelligence. The Union tried it out, using inventor Thaddeus Lowe to head the Balloon Corps. In 1862, Lowe provided valuable intelligence to General George McClellan during the Peninsula Campaign. When other generals replaced McClellan, they were not believers in the balloon corps and seldom used Lowe. Lowe became increasingly frustrated with the army and resigned in 1863.
