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ABSORBENTS

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What substances are called absorbents? What is the most important of these? What substances are called charcoal in agriculture? How is vegetable matter rendered useful as charcoal? Before considering farther the subject of animal excrement, it is necessary to examine a class of manures known as absorbents. These comprise all matters which have the power of absorbing, or soaking up, as it were, the gases which arise from the evaporation of solid and liquid manures, and retaining them until required by plants. The most important of these is undoubtedly carbon or charcoal. CHARCOAL. Charcoal, in an agricultural sense, means all forms.