Pliny: Natural History, Vol. V

51 Columella prioritizes manure from dovecotes, then from the poultry-yard, while condemning the droppings of water birds. Other authors unanimously recommend the residue of human banquets as a primary source; some of them prefer the residue of men's drink, with hair from curriers' workshops soaked in it, while others recommend this liquid by itself, diluted with water—often in larger quantities than when the wine is originally consumed—because a greater amount of toxicity must be neutralized when the human factor is added to the original poison of the wine. These are debated questions, and they even use human waste to nourish the soil. 52 Next to this, they praise the waste of swine, although Columella alone condemns it. Others recommend the dung of any quadruped that feeds on cytisus a type of shrub used as fodder, while some prefer pigeon droppings. Next in value is the dung of goats, then that of sheep, then oxen, and lastly that of beasts of burden.

53 These distinctions were recognized in early days, and I do not find any recent rules for the use of dung, since in this matter also, ancient practices are more serviceable. It has been observed in some provinces, where there is an abundance of livestock, that the dung is passed through a sieve like flour, its stench and appearance being transformed by the action of time into something actually attractive. 54 (It has lately been found that olives particularly thrive on ashes from a lime kiln.) Varro...

possible to be hopeful about our own morals. But Columella puts manure from dovecotes first, and next manure from the poultry-yard, condemning the droppings of water birds entirely. The rest of the authorities advocate the residue of human banquets as one of the best manures, and some of them place even higher the residue of men's drink, with hair found in curriers' shops soaked in it, while others recommend this liquor by itself, after water has been again mixed with it and even in larger quantity than when the wine is being drunk; the fact being that a larger amount of badness has to be overcome in the liquor when to the original poison of the wine the human factor has been added. These are contested questions; and they use man even for nourishing soil. Next to this kind of manure the dung of swine is highly commended, Columella alone condemning it. Others recommend the dung of any quadruped that feeds on cytisus, but some prefer pigeons' droppings. Next comes the dung of goats, after that sheeps' dung, then cow-dung and last of all that of beasts of burden.

These distinctions were recognized in early days, and at the same time I do not find modern rules for the use of dung, since in this matter also old times are more serviceable; and before now in some parts of the provinces there has been so large and valuable a supply of beasts that the practice has been seen of passing dung through a sieve, like flour, the stench and look of it being transformed by the action of time into something actually attractive. (It has lately been found that olives particularly thrive on ashes from a lime kiln.) To the rules given Varro...