Seetee Shock by Jack Williamson. Here is the first paperback appearance of a novel published by Simon & Shuster in 1950. It was serialized in Astounding February, March & April 1949. All magazine appearances and the hardcover edition appeared as by "Will Stewart." This is the second of 2 "Seetee" books - although was the first to be published in book form.

From the front & back covers: "Contraterrene matter - anti matter - looks exactly like our own. The only test is contact, and contact, up until now, has been disasterous. But undismayed by that untouchable stuff, the spatial engineers have named it familiarly seetee, and they are reaching daringly to grasp it now. The mightiest force yet known, it can create a new kind of freedom - the freedom of power. Or, misused, it can crush every human freedom. That is the problem and the promise all our planets face today."

Power Unlimited - Nick Jenkins, seetee engineer, was alone and dying. He was dedicated to the shining goal of supplying free, unlimited energy. But other, less idealistic men had stolen the only stockpile of anti-matter missiles, leaving him to die of shock-poisoning and threatening the solar system with suicidal war. To Nick Jenkins, it almost seemed as the entire universe was his enemy.
Unaided, with only one week left to live, Nick Jenkins had to harness the universe's greatest and deadliest source of energy."