They learned what they could do to help prevent scurvy, typhus and other camp diseases. Bad water and poor sanitation caused the death of many soldiers. Survivors learned the value of proper sewage disposal and the necessity of clean drinking water. They learned how to build shelters to protect themselves from the elements and how to make repeated all-day marches and they also learned the necessity of maintaining their clothes, shoes and weapon. Soldiers had to carry their own gear and weapons and they soon discarded all but the essentials.
Many soldiers even quit carrying extra clothes, just wearing what they had on.
The haversack, a foot-square canvas bag with a waterproof lining, a buckled flap, and a strap that was slung over the right shoulder, became the soldiers' indispensable carryall. It was designed to hold three days' rations, but the men would usually eat them all on the first day rather than carry the weight. This left the haversack free to carry a few personal items and most important, apples, blackberries, and other forage. When the fighting started in 1861, many North and South inventors began producing metal shields, helmets, and vests promoting them as being bulletproof. Soon, however, bulletproof vests and the men who wore them were held in contempt by their fellow soldiers.