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AGRICULTURAL BRANCH LIBRARY 

 ILACKSBURG, VIRGINIA 



Massachusetts 

 Agricultural Experiment Station 



Bulletin No. 341 April, 1937 



Vacuum-Pressure Relationships 

 in Glass Canning Jars 



By C. R. Fellers, A. S. Levine, and W. A. Maclinn 



The present method of canning foods in the all-glass type of fruit jar 

 has several disadvantages, some of which are overcome by a slight 

 change in method of processing. Fundamental data are presented re- 

 garding the nature and development of internal pressures and vacuums 

 in glass containers during thermal treatment. 



MASSACHUSETTS STATE COLLEGE 

 AMHERST, MASS. 



