This was simply an amazing read. Not just space shots, but everything from balloon atmospheric testing to speed sleds to ejection seat testing, we owe so much to our animal assistants. Some of the tests seem laughable (and cruel) today, but we were operating in a vacuum in the 1940s and beyond, and the scientists working with these animals in all countries, both sides of the Iron Curtain, took great pains to make sure that the creatures were well-equipped, physically and mentally, and were kept as safe as possible. Losses of life were mourned by the men and women who spent their every waking hour making these animals comfortable and free from fear. This is a remarkable work.