Minor typographical errors and inconsistencies have been corrected. Some words hadinconsistent hyphenation throughout the book; these have been made consistent.
Ions are shown as Fe+++, instead of using superscripts. There is someinconsistency in the notation used in the original text for chemicalformulæ such as Na2Cr2O7(2H2O).These have been regularized to use the modern mid-dot, for example,Na2Cr2O7 · 2H2O.
The index entry for Hemlock bark had no page number in the original text,so the correct page number, 34, has been supplied.
On page 152 NaCO23 has been corrected to Na2CO3.On page 212, the variable n has been replaced with the correctlysubscripted forms n1 and n2.
ANIMAL PROTEINS
BY
HUGH GARNER BENNETT, M.Sc. (Leeds)
MEMBER OF THE SOCIETY OF LEATHER TRADES' CHEMISTS; FORMERLY
ASSISTANT LECTURER AND DEMONSTRATOR AT THE LEATHER
INDUSTRIES DEPARTMENT OF THE UNIVERSITY OF LEEDS
AUTHOR OF "THE MANUFACTURE OF LEATHER"
LONDON
BAILLIÈRE, TINDALL AND COX
8 HENRIETTA STREET, COVENT GARDEN
1921
GENERAL PREFACE
The rapid development of Applied Chemistry in recent years has broughtabout a revolution in all branches of technology. This growth has beenaccelerated during the war, and the British Empire has now anopportunity of increasing its industrial output by the application ofthis knowledge to the raw materials available in the different parts ofthe world. The subject in this series of handbooks will be treated fromthe chemical rather than the engineering standpoint. The industrialaspect will also be more prominent than that of the laboratory. Eachvolume will be complete in itself, and will give a general survey of theindustry, showing how chemical principles have been applied and haveaffected manufacture. The influence of new inventions on the developmentof the industry will be shown, as also the effect of industrialrequirements in stimulating invention. Historical notes will be afeature in dealing with the different branches of the subject, but theywill be kept within moderate limits. Present tendencies and possiblefuture developments will have attention, and some space will be devotedto a comparison of industrial methods and progress in the chiefproducing countries. There will be a general bibliography, and also aselect bibliography to follow each section. Statistical information willonly be introduced in so far as it serves to illustrate the line ofargument.
Each book will be divided into sections instead of chapters, and thesections will deal with separate branches of the subject in the mannerof a special article or monograph. An attempt will, in fact, be made to[Pg vi]get away from the orthodox textbook manner, not only to make the treatmentoriginal, but also to appeal to the very large class of readers alreadypossessing good textbooks, of w