VI 11 AUTHORS PREFACE. 



such a process of brewing as ni}' stud}' of the subject has 

 enabled me to devise, and from an application of the novel facts 

 upon which this process is founded. Time is the best appraiser 

 of scientific work, and I am not unaware that an industrial 

 discovery rarely produces all its fruit in the hands of its first 

 inventor. 



I began my researches at Clermont-Ferrand, in the labora- 

 tory, and with the help, of my friend M. Duclaux, professor of 

 chemistry at the Faculty of Sciences of that town. I continued 

 them in Paris, and afterwards at the great brewerj'" of Tourtel 

 Brothers, of Tantonville, which is admitted to be the first in 

 France. I heartily thank these gentlemen for their extreme 

 kindness. I owe also a public tribute of gratitude to M. 

 Kuhn, a clever brewer of Chamalieres, near Clermont-Ferrand, 

 as well as to M. Velten, of Marseilles, and to MM. de Tassigny, 

 of Reims, who have placed at my disposal their establishments 

 and their products, with the most praiseworthy willingness. 



L. PASTEUR. 



Paris, June 1, 1876. 



