116 DRAININGS. 



loam around the ground and side-walls. 2d. That 

 it be deep rather than shallow, in order to preserve 

 its coolness, and to expose a small surface of its con- 

 tents. 3d. That it be shut out from the external air, 

 or, in other words, well covered. Lastly, 4th. That 

 it allow no access to the rain. The farmer may find 

 more precise information upon this subject in the lit- 

 tle work entitled, PopuVdre Dungerlehre von Schlipf 

 (Popular Lessons on Manures, by Schlipf). 



2. An addition from time to time of sulphuric acid 

 is beyond all else to be greatly recommended, wheth- 

 er drainings are preserved for themselves alone, or are 

 poured upon the manure-heap in order to keep it 

 moist. It is difficult to propose for a definite num- 

 ber of stock the precise weight of sulphuric acid re- 

 quired for this purpose, say by the week, because the 

 quantity of urine actually furnished to the reservoir, 

 and likewise the condition of the urine itself, depend- 

 ing, as it does, upon foddering, littering, etc., must 

 vary very greatly. As an approximative calculation, 

 it may perhaps be held that a pound of the acid 

 should be mixed with 250 pounds of urine. It 

 would be extremely convenient if a scale of measure- 

 ment was prepared for every recfcptacle, by means of 

 which the weekly increase of the liquid could be 

 easily ascertained, and the addition of sulphuric acid 

 be accordingly regulated. In lieu of sulphuric acid, 

 gypsum, green vitriol, sulphurous coal, or the ashes of 

 pit and brown coal, might be made use of These 

 materials, however, from the circumstance that they 



