MANURES. 161 



most valuable* property of these vegetable absorbents, 

 which is not often thought of. They are carbonaceous 

 — contain much carbon — and they are more or less 

 clayey. Now, carbon and clay are the two things in 

 nature best calculated to take in and hold fast every- 

 thing nutritious to plants, whether gaseous or liquid. 

 From the very day when you throw up a muck heap in 

 your swamp, or by the way-side, it is gathering in for 

 you the food of plants. Farmers always say the older 

 their muck is, the better. There is a very good reason. 

 It is gathering in. It lays the falling rain and the pass- 

 ing wind under contribution, and it keeps what it gets. 

 If a chamber-maid should empty her slops upon a sand- 

 heap, they would escape into the winds, or into the 

 ground, or both. The sand-heap would become no 

 richer. It would retain nothing. But if she should 

 empty them upon a pile of carbonaceous and clayey 

 matter, such as may be found on almost every farm, 

 they would be held fiist. By repeating the process a 

 few days, that pile would become almost as good as 

 guano. Even if nothing were put upon it, it would 

 become better from day to day, by what it would take 

 from the rains and the air. 



301. These vegetable absorbents^ consisting mostly of 

 black, carbonaceous matter, mixed with fine, clayey 

 particles, and acting, as they do, both as absorbents and 

 RETAINERS, aVe of very great value. It must be ad- 

 mitted that they are deficient in the more active salts, 

 as compared with stable manure ; but these, as will be 

 shown hereafter, can be chenply supplied, and then 

 they become almost equal to the best of manures. 



