iv PREFACE 



Several supplementary tables have been included. Of these, Table 6, 

 Mixtures of Air and Water Vapor, will be found specially useful in con- 

 nection with problems that involve hy^mmrtric conditions. 



The Mollicr diagrams for steam and ammonia can be used as a sub- 

 Miiutr for the tables in the approximate solution of certain classes of 

 problems. The use of the diagrams is illu-tiaicd by the examples on 

 pages 27 and 28. 



The author acknowledges his indebtedness to Mr. W. E. Mosher 

 for his cordial consent to the use of the ammonia tables; and to Pro- 

 fessors L. A. Harding and A. C. Willard for many valuable suggestions. 



G - A. GOODENOUGH. 



