-1/2
8 do. |75-1/2|37-3/4|25-1/4|19 |15-3/4|12-1/2|10-3/4| 9-1/2| 8-1/2| 7-1/2
8-1/2 do.|67 |33-1/2|22-1/4|16-3/4|13-1/2|11-1/4| 9-1/2| 8-1/2| 7-1/2| 6-3/4
9 do. |60 |30 |20 |15 |12 |10 | 8-1/2| 7-3/4| 6-3/4| 6
9-1/2 do.|53-1/2|26-3/4|18 |13-1/2|10-3/4| 9 | 7-3/4| 6-3/4| 6 | 5-1/4
10 do. |48-1/2|24-1/4|16-1/4|12 | 9-3/4| 8 | 7 | 6 | 5-1/2| 4-3/4
---------+------+------+------+------+------+------+------+------+------+------

_Example 1._--Required, the number of loads necessary to manure an acre
of ground, dividing each load into six heaps, and placing them at a
distance of 4-1/2 yards from each other? The answer by the table is 39-3/4.

_Example 2._--A farmer has a field containing 5-1/2 acres, over which he
wishes to spread 82 loads of dung. Now 82 divided by 5-1/2, gives 15 loads
per acre; and by referring to the table, it will be seen that the
desired object may be accomplished, by making 4 heaps of a load, and
placing them 9 yards apart, or by 9 heaps at 6 yards, as may be thought
advisable.

FOOTNOTES:

[AC] Under some circumstances, _nitric acid_ is formed, which is equally
beneficial to vegetable growth.

[AD] See the glossary at the end of the book.

[AE] Working Farmer, vol. 1, p. 55.

[AF] It is not necessary that this and the foregoing table should be
learned by the scholar, but they will be found valuable for reference by
the farmer.

CHAPTER VIII.

MINERAL MANURES.

[How many kinds of action have inorganic manures?

What is the first of these? The second? Third? Fourth?

Do all mineral manures possess all of these qualities?]

The second class of manures named in the general division of the
subject, in the early part of this chapter, comprises those of a mineral
character, or _inorganic_ manures.

These manures have four kinds of action when applied to the soil.

1st. They furnish food for the inorganic part of plants.

2d. They prepare matters already in the soil, for assimilation by roots.

3d. They improve the mechanical condition of the soil.

4th. They absorb ammonia.

Some of the mineral manures produce in the soil only one of these
effects, and others are efficient in two or all of them.

The principles to be considered in the use of mineral manures are
essentially given in the first two sections of this book. It may be
well, however, to repeat them briefly in this connection, and to give
the _reasons_ why any of t