The first part of this Book is given up to a review of facts and principles treated in the various Sections on Physics and in the different Sections on Inorganic Chemistry, to all of which the student will be frequently referred. Here, the laws and principles in the above mentioned Parts inside the Book have been more fully treated, in order that further study may be facilitated and the study of Organic Chemist better understood. It is imperative that the student give careful attention to Organic Chemistry, for it is by no means an easy subject. He should not rest satisfied with merely reading this Book, but should give it thorough study and frequent review, for, once mastered, the principles here taught will be of great assistance in future work.