62

A DISCOURSE

Wood-ashes, rich and impregnate with salts, are fit for wet groundwithout mixture, and in pasture excellent, not sifted on over thick. Inthe West Indies near Guatimala, Gage tells us their manure is the burn-ing of trees to ashes p . These kill the worm; but in earth which issubject to over-heat and chap much, ashes and burning composts do butincrease the fever, and therefore contrary remedies are to be sought, suchas the dung of oxen and swine; but not so when lands are naturally or ac-cidentally cold. Wherefore we should endeavour by all means to detect, asfar as we are able, the quality predominant both of the earth we wouldimprove, and the composts we apply, and not throw them promiscuouslyupon every thing without considering of what temper and constitutionthey be ; for grounds are as nice as our bodies, and as obnoxious to in-firmities upon every defect and excefs; and therefore it requires skill, andno little study, to be able rightly to marshal this Materia Medica (as I maycall it) of composts, the virtue of which does sometimes lie very hidden;at least, if it be true which Sir Hugh Platt affirms, that what we all this

while Seek after, is indeed, altogether invisible to Human eyes, and to be

discerned only by the eyes intellectual, because it is veiled and clad underso many different bodies, whereof some are more ponderous, such asmarl, chalk, the dung of beasts, &c.; and some more light, as their flesh,bones, hair, &c.; and some yet lighter, as grain and generous seeds: forin such as have virtue to multiply their own species, that spirit is investedwith a very thin and curious integument, as in effect we have instancedin the blood and flesh of animals, so much more powerful for the enrichingof land than their dung and excrements—this industrious man computingit to no lefs than twenty times; and to the same advance above this, hair,wool, and calcined bones q . As to the coarser soils, he says, that the

P In Sweden, Finland , Livonia, and the greatest part ofRufsia, where woods are plen-tiful, the countrymen cut down large tracts, and after burning the wood they sow the landwith corn, which husbandry they continue for three years, the wood ashes remaining inforce for that time. On the fourth year they remove to another woody quarter, and inthis manner they proceed till the first sown land be again covered with wood, which isgenerally in about twenty years. This operation is called in the north, Swedieland, SeeOsbeck’s Voyage to China , p. 50. vol. 1.

q Bones should by no means be calcined, as their virtue is difsipated by the fire, andnothing but a caput mortuum left behind. My worthy friend, Gen. St. Leger, has favouredme with the following account of bones used for manure. The subject is curious as wellas important: '

“ Eight years ago I laid down to grafs a large piece of very indifferent limestone land