What form of anesthetic was used during field surgery in the civil war?

The only anesthetics they had during the Civil War were whiskey

• you were supposed to get so drunk you couldn't feel a thing - and

chloroform, which is inhaled. The chloroform killed the pain but didn't render you unconscious; Stonewall Jackson reported that he could hear them amputating his arm but not feel it. Because they didn't know how much chloroform to give a patient, some casualties died from chloroform poisoning.