MANURES. 225 



its efficiency. But it must be air dry, or it will not fully accom- 

 plish its purpose. 



The best and cheapest drying apparatus is the sun and wind 

 of a summer day. During a drought the parched surface of 

 naked land is in precisely the condition needed for use, and a 

 year's supply may then be taken into a close out-building or a dry 

 cellar, and stored until wanted. 



Those who have not made, or cannot make, this provision, 

 may store damp earth in a well-ventilated dry place, from which 

 mists can be excluded, and in a shorter or longer time, according 

 to the climate, it will become dry — just as bread so kept would 

 do. The writer has had a commode in constant use for nine 

 months, and nearly all of his winter's supply of earth has been 

 dried and redried in a hogshead lying on its side,- its open end — 

 facing the south — being protected from rain and mist by a close 

 screen of rough boards leaning against it. The sun had very 

 little chance at it, but the wind had, and the drying has been 

 sufficiently rapid for such a limited supply as is needed for one 

 commode. 



At the experimental station of the United States Engineers (at 

 Fort Adams) there is in use a sort of hot bed raised a little from the 

 ground with a broad floor, and provided with movable sashes bat- 

 tened at the joints. The earth is thrown loosely in to a depth of 

 about six inches, and whenever a drying wind blows, the sashes are 

 raised at both ends. In damp weather they are kept close, and 

 when the sun shines, without there being much wind, they are 

 raised at the back only enough to allow the escape of the moisture 

 evaporated. This plan is cheap, simple, and perfectly effective. 



To dry the earth in a more systematic way, especially for the 

 supply of towns or large factories, it will be necessary, particu- 

 larly in winter, to employ the aid of fire heat. The scale on 

 which this is to be done must determine the extent of the appli- 

 ances for the purpose. Earth enough for the use of a family may 

 be dried in a shallow box near the furnace, or the kitchen stove 

 or range. For the supply of larger establishments or for towns, 

 when the requisite quantity of earth has not been stored in the 



