PART 1 



GENERAL BACTERIOLOGY 



CHAPTER 1 



HISTORICAL OUTLINE 



In the study of any branch of science, an acquaintance with the historical develop- 

 ment of knowledge is an important element in a clear understanding of our present 

 conceptions. To the student of bacteriology such a basis is essential. It is almost 

 true to say that the clue to the present position of bacteriology is the curioup fact 

 that there have been no bacteriologists. From Pasteur onwards, the great majority 

 of investigators have been more interested in what bacteria do than in what they are, 

 and much more interested in the ways in which they interfere with man's health or 

 pursuits than in the ways in which they function as autonomous living beings. The 

 relations of bacteria to disease, to agriculture, and to various commercial processes, 

 have presented problems which pressed for solution ; and, as a result, we have 

 witnessed a reversal of the normal process. We have seen the development of an 

 applied science of bacteriology, or rather its application along many divergent 

 lines, without the provision of any general basis of purely scientific knowledge. 

 The essential interlocking of pure and applied science has, of course, been in 

 evidence here as elsewhere. The necessity for being able to recognize a bacterium, 

 which has been shown to be of importance m some province of human affairs, 

 or of determining the way in which its harmful or beneficial action is brought 

 about, has led to an intensive study of many aspects of bacterial morphology 

 and physiology ; but, in general, it may be said that the study of bacteria them- 

 selves has been carried out en passant, that amount of knowledge being acquired, 

 or searched for, which would afiord adequate data for the solution of some problem 

 in applied bacteriology. Gradually the general structure of our knowledge has 

 been added to, and gaps have been filled. Many of those who have started from 

 some particular application have been led far afield by that desire for knowledge, 

 altogether apart from its technical application, which is the essence of science 

 itself. But this mode of construction has given to the general body of existing 

 bacteriological knowledge a curious patchiness and indefiniteness which are puzzling 

 to the student, and which must be realized and allowed for in any attempt to 

 present the subject as a whole. There can be no question of any future recon- 

 struction ab initio. The history of a science is largely a history of technique, and 

 the foundations of bacteriological technique, which presents many peculiar difii- 

 culties, have been well and truly laid by those who have worked in this field since 



P.B. 1 B 



