What advances in Technology were brought about and hastened by necessity during the Civil War?

Answer 1

Finally a inventive great question: The Civil War brought many innovations to Warfare; Trench War Fare, Torpedoes (land mines), Aerial observation, Submarines, Rifled Weapons,
Armored Ships, Railroads, Telegraphs, Artillery and Maneuvers. God Bless You and The Southern People.

Answer 2

1. Care of the wounded - development of field hospitals, sanitary practices [the fore-bear of today's "universal precautions"]

2. Transportation -

3. Some weapons development, but not as much as you'd think. Breech loading rifles were known before the War, but not adopted because of bureaucratic inertia.

Good question

Answer 3

The biggest one I can thing of is the steam driven ironclad. Add a movable turret for guns and you have something very modern as opposed to sail driven ships of the line.