438 THE CAUSES OF THE XI 
You will see from this that, at the end of the 
first year the single plant will have produced fifty 
more of its kind; by the end of the second year 
these will have increased to 2,500; and so on, in 
succeeding years, you get beyond even trillions; 
and I am not atall sure that I could tell you what 
the proper arithmetical denomination of the total 
number really is; but, at any rate, you will under- 
stand the meaning of all those noughts. Then 
you see that, at the bottom, I have taken the 
51,000,000 of square miles, constituting the sur- 
face of the dry land ; and as the number of square 
feet are placed under and subtracted from the 
number of seeds that would be produced in the 
ninth year, you can see at once that there would 
be an immense number more of plants than there 
would be square feet of ground for their accom- 
modation. This is certainly quite enough to 
prove my point; that between the eighth and ninth 
_ year after being planted the single plant would have 
stocked the whole available surface of the earth. 
This is a thing which is hardly conceivable—it — 
seems hardly imaginable—yet it is so. It is 
indeed simply the law of Malthus exemplified. 
Mr. Malthus was a clergyman, who worked out 
this subject most minutely and truthfully some 
years ago ; he showed quite clearly—and although 
he was much abused for his conclusions at the 
time, they have never yet been disproved and 
never will be—he showed that in consequence of 
