PREFACE TO THE NEW EDITION 
IN THE preparation of a new edition of Milk and 
Its Products, in addition to making such changes as 
are necessary to bring the body of the work up-to- 
date, it has seemed well to add chapters on dairy cat- 
tle and the production of milk, on certified milk, and 
on ice-cream manufacture. Brief directions for sim- 
ple bacteriological determinations have also been 
added. The latter has been prepared by my daughter, 
Lois W. Wing, late assistant in dairy bacteriology, in 
the New York State College of Agriculture. The 
chapter on certified milk was written by Mr. George 
C. Watson, formerly manager of the Tully Farms, 
and grateful acknowledgment is hereby made to both 
for their assistance. 
HENRY H. WING. 
New York State College of Agriculture 
Cornell University, July, 1912 
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