1 Sepr., 1901. ] QUEENSLAND AGRICULTURAL JOURNAL, 291 
are not alike—all do not contain the same amount of plant-food (Lesson 3). 
Ifyou were to sow wheat in pure sand, or potatoes on stiff yellow clay, you 
would not expect to get a good crop of either; but there are soils which, 
whilst they will produce crops of a certain kind, yet are not suitable for those 
which require a large amount of solid nourishment. 
Again, you have seen that there are soils so rich in plant-food that farmers 
keep on planting and sowing the same crops on them year after year, without 
reflecting that every crop takes out a certain quantity of the various plant- 
foods, and that therefore the land becomes poorer every year. Now, if you 
take some flour out of the flour-bag every day and put no flour back, or if you 
keep on paying away money out of your pocket without putting back what 
you have spent, you will before long get to the bottom of the bag or of your 
pocket, and will, when it is too late, begin to wonder why you haye no more. 
So it is with the soil. Each time a crop is taken off it takes with it all the 
ingredients which have built up the plants. If these materials are not replaced 
in some way, it’is clear that after a time, longer or shorter, according to the 
natural fertility of the soil, the whole of the plant-food which the roots can 
reach will be carried away, and the land becomes at last like your pocket— 
unproductive. If there were no easy means of putting back what has been 
carried away, then farming could not be carried on unless every farmer had 
hundreds of acres of new land which he could plough up and plant when the 
old fields were useless. But even with thousands of acres the time must come 
when the whole would be worn out, and then what would beeome of the 
farmer? What, indeed, would become of the world? How would men and 
beasts live when the farmer would no longer produce wheat and barley and 
oats ? 
There is a saying in the good old Book: ‘“ The King himself is served by 
the field.” And this is actually true. The whole business of the world, all the 
Governments, all soldiers and sailors, are kept in existence by the labours of the 
farmer, who is thus the mainspring of all. 
But wisdom has been given to men to learn how to restore the fertility of 
the soil, and thus it happens that land which has been farmed for over 3,000 
years still produces even better crops of all kinds than in olden times. 
How this fertility is maintained is what you have now to learn. By and 
by we shall study the subject in its more advanced stage. All plants contain 
certain minerals and gases. Many of these are drawn from the soil, and, as I told 
you, must be returned to the soil in some form or other in order that nothing 
may be lost. It was long ago found out that stable and farm-yard sweepings 
contain all that isneedful to give back to the land the ingredients taken out by 
the crops it has borne. These sweepings are termed farm-yard manure, and. 
when this manure is carefully preserved and ploughed in to the land in 
sufficient quantities, the next crops sown will find ready at hand all the plant-food 
necessary to produce a good harvest. 
But the use of manure is only one of the means adopted by the farmer to 
keep his land fertile. You have heard of very hard-worked men requiring a 
Rest. Business men, and men who work hard with their brains, must all rest 
sometimes, or they would become ill. You know that holidays are always given 
to school boys and girls. Why is this? It is because neither teachers nor 
scholars can keep on during the whole year with brain-work. There must be a 
time of rest to enable them to regain the brain power which becomes exhausted 
by continued work. 
Well, the soil also requires rest, in order to recover from the exhaustion 
paused by continually producing crops. What is meant by “exhaustion” is 
this :— 
When a soil has been put out of condition by continually cropping year 
after year without sufficiently manuring it, it is said to be exhausted, although 
