Royal Society. 37^ 
tliat the land can bring forth no more of that kind, it may after- 
wards yield CTood oats, and perhaps peafe after all thefe- at 
length it will become barren, the vegetative matter, that itatfirfl 
abounded in, being extrailed from it by thole fucceffive crops, 
and mofl of it borne off 5 for each fort of grain extracts from it 
that peculiar matter that is proper for its own nourifhment: After 
all this, that very tradl of land may be brought to produce another 
lerics of the fame vegetables 5 but never till it is lupplied with a 
new fund of matter, of like Ibrt with that it at firll contained - 
which fupply is made feveral ways, either by the ground's lying 
fallow fome time, till the rain has poured down a frefh ftock 
upon it, or by the farmer's care in manuring it : And for fur- 
ther evidence that this fupply is in reality of a like fort, we 
need only refled^ a while upon thofe manures that are found 
by conftant experience, belt to promote vegetation and the fruit- 
fulnels of the earthy and thefe are chiefly parts of vegetables 
or animals, which indeed derive their own nourifliment imme- 
diately either from vegetable bodies, or from other animals that 
do io 5 in particular the blood, urine and excrements of animals, 
ihavings of horns and of hoofs, hair, wool, feathers, calcined 
Ihell"^, lees of v/ine and beer, afnes of all forts of vegetable 
bodies, leaves, ftraw, roots and ftuhble turn'd into the earth by- 
plowing or otherwile, to rot and diifolve there, all theie prove 
the beft manures, and being vegetable lubftances, when refunded 
back again into the earth, ferve for the formation of other like 
bodies : We meet with fliil further confirmations of the fame 
thing in our gardens, the trees, fhrubs, and herbs cultivated 
there, after they have continued in one Ifation, till they have de- 
rived thence the greater part of the matter proper for their in- 
creafe, will decay and degenerate, unlefs either fre-h earth, or 
fbme proper manure be applied to them: it is true they may 
maintain themielves there for fome time, by fending foith roots 
further and further to a great extent all around, ro ictcn in more 
remote provifion 5 but at lafl all will fail, and they muft either 
have a frelh lupply brought to them, or they themfelves be 
tranfplanted to lome places better furnilaed with matter for their 
fubfiiience ^ and accordingly gardeners obferve, that plants that 
have ftood a gre^t while m a place, have longer roots than uluaJ, 
part of which they cut off, when they tranlplant them to a freih 
Ibil, as now not of any further uie to them , io that ail theie in- 
ftances, and .a great many others that might be alledged, point 
forth a particular terreftrial matter, and not water only, for the 
fubjed to which plants owe their increaie 5 for were it water only, 
there 
