Supposing the garden to contained an acre, and the laborer to earn a dollar a day, the cost of this operation will, of course, be forty dollars; which, perhaps, would be twenty dollars above the expense of the various ploughings and harrowings, necessary in the other way; but, the difference in the value of the two operations is beyond all calculation.

There is no point of greater importance than this, poor ground deeply moved is preferable, in many cases, to rich ground with shallow tillage; and when the ground has been deeply moved once, it feels the benefit for ever after. A garden is made to last for ages; what, then, in such a case, is the amount of twenty dollars?

It is well known to all who have had experience on the subject, that of two plants of almost any kind that stand for the space of three months in top soil of the same quality, one being on ground deeply moved, and the other on ground moved no deeper than is usual, the former will exceed the latter one half in bulk.

And, as to trees of all descriptions, from the pear tree down to the currant bush, the difference is so great, that there is room for no comparison. It is a notion with some persons, that it is of no use to move the ground deeper than the roots of the plant penetrate.

But, in the first place, the roots go much deeper than we generally suppose. When we pull up a cabbage, for instance, we see no roots more than a foot long; but, if we were carefully to pursue the roots to their utmost point, even as far as our eye would assist us, we should find the roots a great deal longer, and the extremities of the roots are much too fine to be seen by the naked eye.

Upon pulling up a common turnip, who would imagine, that the side, or horizontal roots, extend to several feet? Yet I have traced them to the length of four feet; and Mr. Tull proved, that they extended to six feet, though he could not see them to that extent with his naked eye.

But, though the roots should not extend nearly to the bottom of the moved ground, the plants are affected by the unmoved ground being near at hand. If this were not the case, plants with very short roots might be cultivated on a brick pavement with earth laid upon it to the thickness of a foot; and yet, no plant will live and thrive in such a state, while it will do very well in ground along side the pavement, though moved only a foot deep.

Plants require a communication with, and an assistance from, beneath as well as from above, in order to give them vigor and fecundity. Plants will live, and will grow to a certain extent in earthen pots, or in boxes made of wood; but, there must be holes in the bottom of both, or the plants will die.

It is, therefore, of the greatest importance, that the ground be moved to a good depth, and, he who is about to make a garden should remember, that he is about to do that, the effects of which are to be felt for ages.

There is, however, one objection to trenching in certain cases. The soil may not only not be good to the depth of two feet, bit it may be bad long before you come to that depth and, in this case, the trenching, in putting the good soil at bottom, might bring a hungry sand, or even a gravel or clay to the top, which must not be done by any means; for, even in the case of trees, they would perish, or become stunted, because their roots would not find their way from the bad soil to the good.

Your first trench must be opened in the manner described in that paragraph; but you must not then proceed to turn the top of the next two feet into the bottom of the trench. Let us suppose, now, that you have your first trench, two feet wide as before directed, open and clean. This being the case, take a foot deep of the next two feet all tile away along, and, for this once, throw it over the open trench to add to the earth that you have already thrown out of that trench.

Then you will have the bottom, foot of earth left. Dig out this and turn it into the bottom of your open trench, and then the first trench will be half filled up, and you will have got your second trench open.

Then go to a new two feet wide, that is the third two feet. Take the top foot deep off from this, and throw it on the top of the earth that you have just turned into the first trench; and then, where that first trench was there will be earth two feet deep; the bad soil at bottom and the good soil at top.

Then you go on regularly. The bottom foot of the fourth two feet wide piece you turn into the bottom of the second trench, and the top foot of the third two feet wide piece you throw on the top of the earth which is at the bottom of the second trench.

And, thus, when you have done, you will have moved all your ground two feet deep, and will have the bad soil at bottom and the good at top.

At the end of your work, you will, of course, have an open trench and a half; and this must be filled up by carrying the earth, which came out of the first trench, round in a cart or wheel barrow, and putting it into the space that you will have open at last.