PREFACE 



TO 



THE THIRTEENTH EDITION. 



A TREATISE that made its original appearance in the first 

 decade of the century, and that enters upon its Thirteenth 

 Edition before the century has run its course, may be con- 

 sidered to have established its claim upon public favour. 



In preparing this modernised and enlarged edition, therefore, 

 it has been deemed expedient to retain, as far as possible, those 

 features of Youatt's work which must have commended them- 

 selves to the genera] approval. Accordingly, very little altera- 

 tion has been made in the scheme of the original volume, so 

 that the treatise continues to be divided, as heretofore, into 

 Books, and, saving that an additional Book has been intro- 

 duced, the arrangement is the same as in the Twelfth Edition. 

 To a considerable extent the sub-divisions of the several Books 

 have likewise been retained. 



It should be noted, however, that in giving to the various 

 subjects the full treatment demanded in view of the phenomenal 

 progress of the last dozen years, it has been found necessary to 

 practically rewrite the work, and to enlarge it from some 900 

 to about 1100 pages. Entirely new chapters have been added 

 on the Secretion of Milk (Book the Second), on the Anatomy 



