PREFACE TO THIRD EDITION 



In making such alterations as seemed called for in the prepara- 

 tion of this edition, an attempt has been made to avoid as far as 

 possible any further expansion. It has been thought, however' 

 that a brief account of the methods of preparing bacterial vaccines 

 should be inserted : not that the practitioner should necessarily 

 make them for himself, but so that he may have a general idea 

 of the process. Of the other changes made, the main are an 

 account of making cultures of the blood by the use of an all- 

 glass exploring syringe, fuller details concerning lumbar puncture, 

 the diagnostic value of this operation in uraemia, and the use of a 

 Dewar's flask as an incubator. 



Some of the coloured plates have been redrawn, and- Figs. 31, 

 34, and 45 (for which I have to thank Mr. R. Gompertz) added. 

 My thanks are also due to Dr. H. B. Day for Figs. 16, 17, and 

 26, and to Messrs. Down Bros, for Fig. 30. 



W. D'ESTE EMERY. 

 June, 1908. 



