PREFACE. 



THE rapid progress of discovery in the last 

 few years has created a very general interest in 

 bacteria. Few people who read could be found 

 to-day who have not some little idea of these 

 organisms and their relation to disease. It is, 

 however, unfortunately a fact that it is only their 

 relation to disease which has been impressed upon 

 the public. The very word bacteria, or microbe, 

 conveys to most people an idea of evil. The last 

 few years have above all things emphasized the 

 importance of these organisms in many relations 

 entirely independent of disease, but this side of 

 the subject has not yet attracted very general 

 attention, nor does it yet appeal to the reader 

 with any special force. It is the purpose of the 

 following pages to give a brief outline of our 

 knowledge of bacteria and their importance in 

 the world, including not only their well-known 

 agency in causing disease, but their even greater 

 importance as agents in other natural phenomena. 

 It is hoped that the result may be to show that 

 these organisms are to be regarded not primarily 

 in the light of enemies, but as friends, and thus 

 to correct some of the very general but erroneous 

 ideas concerning their relation to our life. 



MIDDLETOWN, April /, /<?97. 

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M336376 



