Book excerpt: This monograph is concerned with systematization of the infrared spectra of an important natural polymer, cellulose, and its derivatives. The infrared spectra of the main classes of cellulose derivatives are de scribed and interpreted and those of such model compounds as mono-, di-, and trisaccharides are considered. Considerable attention is given to prob lems of technique in obtaining infrared spectra of fibrous cellulose materials, and to the analytical possibilities of infrared spectroscopy in studies of the properties of cellulose and its derivatives. The book will be of use to scientific and plant workers interested in the study and treatment of cellulose, compounds related to cellulose (carbo hydrates and polycarbohydrates), and other polymers. v INTRODUCTION Spectroscopy has nowadays acquired great scientific and practical im portance. Its possibilities are based on the specificity of the emission and ab sorption spectra of all types of material, from elements to complex natural products. Most widely used are the methods of emission spectral analysis (analysis of the emission spectrum from an incandescent body). The rapidity and availability of these methods, together with their high sensitivity and selectivity, has made them indispensable in the practice of plant and scien tific laboratories for establishing the presence of specific elements in a sub stance under investigation.