JUNE 1917 Mustard gas! A feeling of panic hit me and I scrambled to get my respirator over my face before the killer gas got into my mouth and nose and burnt my lungs. It burned everything it touched. Eyes. Skin. And it always found a way in. Like now, I could feel where it had crept up inside the sleeves of my uniform and the skin on my arms felt like it was on fire. I threw myself into a muddy hole, pushing my arms under water, but I knew it was already too late. I stumbled to my feet, saturated, with the weight of wet mud clinging to me. I couldn't move. I couldn't see...