fowing, but when they were fit to dig, I found them vaftly inferior to those I had eat with the gentleman, who furnished me with the feed.

This degeneration (if I may use the expreffion,) did not proceed from a difference in foil or tillage, both being equally good, and equally attended to, but from the weakness of the potatoes, their ftrength having been exhausted by fucceffive fhoots, before I had received them.

Few potatoes preferve their originality, because they exhauft themselves before they are fown. To preferve them in their best ftate, they should be fown fo foon as they begin to vegetate; if this be not attended to, the potatoe tillage will dwindle, and inftead of large potatoes, and a good crop, which the countryman flatters himself, that rich manure and good tillage muft produce, he will find his potatoes small, and ofttimes scarce worth digging. This kind of tillage we may daily fee with the poor cottiers; they have given up their time to their landlords, whofe tillage must first be attended to, leaving their own potatoes

potatoes in heaps in the field, till they have fpent themfelves.

The apple potatoe is the only kind in general, that preferves its originality, becaufe its fhoots are not fo forward as the others, and are fit for fowing, when all other kinds are in ground, and the poor man ready to till: this should be called the poor man's potatoe, because Providence has, in a most kind and benign manner, withheld its fhoots, till he has time to begin his tillage.

I fhall beg leave to remark, that every kind of potatoe should be fown separately; if they be not, but fown with different kinds, they from contact participate of the quality of each other, and produce but a fpurious kind of potatoe; this obfervation may in fome measure be verified in the culture of red cabbage: if you fow it in the fame bed with the green, or even tranfplant it near to the green, the green shall be impregnated with the red, and the originality of both will be hurt; but by fowing each in beds remote from each other, each kind will be preserved in its own diftinct fpecies, without any intermixture

F

mixture of colour. I have frequently observ. ed this alteration in potatoes, where a good kind has been fown and in contact with a bad, that the good potatoe has had one half of it impregnated with the bad kind, agreeable to the idea of the * Roman poet relative to the grape:

"Uvaq; confpectâ livorem ducit ab uvâ."

which contact, perhaps, on due investigation, may be found to be the fource of that degeneracy or alteration, which prevails in other parts of the vegetable fyftem.

In my former letter to the Dublin Society, I endeavoured to fhew, that the ftrength of the potatoe lay in the fhoots': we may by analogy, (if I may be fo bold,) compare it to the first shot of liquors of every kind. The vin de goute is but the first running of the grape, before it is preffed, and produces a liquor, much stronger than that, produced by preffing. The firft droppings of the apples before they have been preffed, yields the beft and strongest kind of cyder; and the first fhot from the ftill, a fpirit, fuperior to that from the feints. I do not know how far this analogy

Juvenal.

analogy may apply to the ftrength of the fhoots, I mention it only as a fecondary illustration; for the fhoots that proceed from the potatoe early in fpring, exhaust its strength, and produce a fuperior kind; whereas if fuffered to fpend themselves, the original quality is deftroyed, as liquors are rendered weak, by being drawn too fine.

I shall here beg leave to obferve, that every perfon adopting this mode of culture, fhould ftrictly follow the directions laid down, if he wishes to have a good crop. Good covering is the very life of potatoe tillage; this is an obfervation founded on experience, though little attended to; and the reafon why potatoe tillage is in general fo poor, is, because they think a light covering of an inch or two fufficient, without ever confidering, that the potatoes afcend to the furface, and the more covering, the greater the produce: this I have experienced in 'thofe fhoots planted in drills, for the potatoes have afcended on the stock, each covering producing an additional layer, and the whole drill appearing as one continued heap of potatoes. This proves to a demonstration the fuperior advantage of the F 2 drill

drill culture; but if the tiller be wedded to his old fyftem of fowing in beds, even in this mode, he can greatly avail himself, by planting the fhoots in holes made by the dibble. A tenant of mine by my directions, tried it last fpring, and the potatoes were larger, and more in number, than thofe produced from the fculliane.

The potatoes afcending to the furface on every covering, led me to confider the green ftock, and its vegetative quality: I ordered my labourer to make a drill in the month of June, and finding fome stocks more luxuriant than others, I cut them in the middle, and planted the tops fix inches deep, leaving about four inches above ground, landing them as in the former inftances. In the month of De. cember I dug them out; they were as large as the common run, but not equal in number to those produced from the fhoots. This is a measure I would not recommend. I watched the ftocks from whence the tops were taken, and found they were not injured in the least, and as great produce under them, as if they were not cut: this experiment I mention to fhew, that we are ftill ignorant, and stran

gers