500 The Storage of Farmyard Manure 



that the manure from different kinds of beasts should be kept separately, 

 but if corn only was being grown there was no necessity for this. 

 Thus, three guiding rules were laid down : 



1. The manure must not be allowed to become dry, 



2. It must be rotted before being applied to corn, 



3. If possible the different kinds of manure must be kept separately. 

 Succeeding writers — Cassianus Bassus who compiled the Geoponica 



about the middle of the tenth century, Crescentius in the thirteenth 

 century, and the writers of the Renaissance period — generally transcribed 

 Varro and Columella without always quite understanding them, and 

 added so little that the three rules just given were almost universally 

 quoted right up to the experimental times of the eighteenth century. 



Neither Varro nor Columella had anything to say about the bad 

 effect of rain on the manure heap : their whole concern was to prevent 

 it from getting too dry. No doubt in Italy the heap was more likely to 

 suffer from sun than from rain. In England and North Europe the 

 case was different, but as the agricultural teaching was derived from 

 the Latin writers no account seems to have been taken of this difference, 

 and we can find no particular recommendation to guard against rain. 

 It is impossible to estimate how much was lost to mediaeval man by 

 the strict adherence to the instructions of Columella in spite of the 

 difference in conditions be{;ween Roman and North European husbandry. 



Mortimer^, one of the most polished writers of his day, recognised 

 that rain was harmful but he was much too good a student of Columella 

 to leave out the instructions with regard to the making of the pit. 

 " The common way (of making a manure heap) is by laying of the Dung 

 in heaps till it rots ; but the way that v/ould be most profitable to the 

 Husbandmen is to make near his House or Barns a large pit... and to 

 pave it with Stone or Chalk that it may detain the moisture of the 

 Dung...." Then he breaks away from the classical instruction and 

 adds- — "but if you can have a covering over it so as to keep all the 

 Rain-water out of it. . .it will much improve it : For the Rain-water that 

 runs from it, carries away the Salt of the Dung with it, which is the 

 chief cause of its fertility. But if you cannot have such a conveniency, 

 Jay it as thick on heaps as you can, and in the moistest lowest places 

 you have, covering the top of it with Turf or other Earth to prevent 

 the Sun or Wind from extracting and drying the virtue of it:... for the 

 better and greater the quantity of your Dung is, the better will be your 



1 The Whole Art of Hiishandry, by J. M. Esq., F.R.S., 1707, p. 96. In later editions 

 the author gives liis full name. 



