4 THE GENERAL CHARACTERS OF MICROORGANISMS. 
tant than the pathological side. If the medical student needs to 
know something of these organisms and their relations to disease, 
even more does the agriculturist need to understand their relations 
to his industry. These microorganisms play such a fundamental 
part in the processes of nature that the life phenomena of animals 
and plants are inextricably bound up in the functions of bacteria, 
and without them life processes must soon cease. The physician, 
in the curing of disease, gains a certain advantage from his knowl- 
edge of bacteria; but the farmer is obliged to make use of these 
agents in a large number of his farming processes; hence, it is a 
matter of necessity that the agriculturist of the future should have 
a practical knowledge of the general phases of bacteriology. The 
solution of the most vital agricultural problems, like that of continued 
soil fertility, involves bacteriology. From beginning to end the 
occupations of the farmer are concerned in the attempt to obtain the 
aid of these microorganisms where they may be of advantage, and 
to prevent their action in places where they would be a detriment. 
The farm cannot be properly tilled unless the farmer has, in addi- 
tion to his seed crop and cattle, a stock of the proper kind of bacteria 
to aid him in preparing the soil and in curing the crops. Farming 
without the aid of bacteria would be an impossibility, for the soil would 
yield no crops. 
The relation of microorganisms to farm life is one of the most 
recent branches of science. Scarce twenty years have elapsed since 
the first steps in this direction were taken, and some of our scientists, 
who are still young, have seen practically the whole development of 
the subject from its starting-point in the early eighties. With a 
science as young as this, it is inevitable that many questions remain 
unsolved. Scientific discovery usually precedes any practical 
application, and in these early years of the development of agricul- 
tural bacteriology we must expect to find the theoretical side of the 
subject proceeding rapidly, while the application of the facts to 
farm methods lags behind and is, in many respects, hesitating, 
tentative, of even unsatisfactory. Nevertheless, the discover- 
ies made have already revolutionized agricultural processes. 
Changes in agricultural methods, due to bacteriology, have been 
