ll PREFACE 
my cautions and advice to learn navigation 
before buying your ship, is to blow against the 
North wind. 
If you have skipped the foregoing, just skip 
again, back to it. You will see that I have 
promised to use no scientific terms. This 
book will be read by more plain people than by 
scientists, and so I have aimed to talk just as I 
would if I were trying to teach you how to 
raise lettuce—or rather trying to teach you to 
learn for yourself how to raise lettuce. For 
we cannot teach anyone anything, we can only 
give him the opportunity of learning. So if 
the experimental agriculturist thinks that a 
good deal has been left out that might have been 
put in, I hope he will remember that I have had 
to pick from a measureless field, and by trying 
to crowd in too much I might easily confuse the 
less experienced and make it hard for him to 
learn. 
And yet no one need think that by reading 
a book or any number of books he can be made 
a gardener. That is done by work of head and 
hands on the soil; and the best preparation 
for a really scientific use of your own land, is, 
to hire yourself out for a while to a market 
gardener and get the practical, every-day 
experience. 
