Unlike some other reproductions of classic texts (1) We have not used OCR(Optical Character Recognition), as this leads to bad quality books with introduced typos. (2) In books where there are images such as portraits, maps, sketches etc We have endeavoured to keep the quality of these images, so they represent accurately the original artefact. Although occasionally there may be certain imperfections with these old texts, we feel they deserve to be made available for future generations to enjoy.

A rich collection of early works useful for the history of chemistry, particularly in alchemy. Detailed bibliographical descriptions. Frequently mentioned are other editions, translations, and additional works of an author which are not included in the Young collection. Biographical information and an evaluation of an author's work are added features.