The discovery and study of the trans uranium elements is one of the latest and most vital extensions in chemistry. With these discoveries, man has been able to create new elements. Exemplary of these new elements is plutonium, the second trans uranium element discovered. It was the first synthetic element seen by man and the first example of large-scale production of an element by transmutation. In writing this book, I have had in mind readers equipped with an understanding of the basic principles of physic and chemistry, although Part 1 can be read with profit by those with less preparation than this. It is hoped that this treatment aspects of post-World War 2 chemistry will encourage further exploration by the reader. A list of references is therefore supplied at the close of the book. The chapters which follow are grouped into two parts. The first deals with a chronological and comprehensive survey of each of the eleven transuranium, elements discovered before 1963. Part 2 offers a more detailed account of the chemical and physical parameters of the actinide elements and investigates the sources of these elements.