During the past twelve years my statements of the success or failure of attempts to graft the vine have appeared in the horticultural journals, but the precise conditions of success have not yet been clearly pointed out. A few operators have been so generally successful that they consider failure the rare exception to the rule; but the instances of general or entire failure have been far more numerous.

To state the conditions of success in brief, I would say, the stock and scion most be brought together under circumstances favorable to vegetation, with the stock actively disposed to form granulations, and the scion disposed to the formation of callus at the same time. The bud of the scion will soon shoot forth, and if not protected from the hot sun or drying wind, will probably soon perish. After the inosculation of callus and granulation, vegetation goes on in the rapid formation of shoot for a considerable time before a union takes place, during which time the shoot has not much power of endurance, and can not be left unguarded with safety. Even at the end of a season, and after vigorous growth has been made, the union is often slight. The motion of the watery sap of the vine (for sap we will call it) is often very energetic, and pushes forth its shoots before it carries enough nutriment to add to its incipient root, or form granulations on a mutilated part.

If under these circumstances, the operation is well performed, the bleeding will go on through the scion, which will shoot, and appear to grow for a season, and the new operator will entertain no fear as to success; and if the season is warm and dry, and the stock and graft are both in perfect condition, there is some ground for hope, in proportion to latitude and climate. The operation which will succeed at Cincinnati will fail at Cleveland, in the hands of the same operator. If the season should be cold or rainy, the water will continue to flow, and no granulations form. To obviate this, the operation is deferred until the season is advanced, and shoots have put forth to the length of three or four inches. The scion for this purpose must be kept back, so that the bud is swelling, but not pushing. If the conditions already named are satisfied, and if the stocks are good healthy Isabellas or Catawbas, the operation will generally succeed; but the farther north, the more advanced must be the shoot, often to the time of inflorescence.

The conditions favorable to success are fine healthy stocks of Catawba, Clinton, or Isabella, etc.,., with vegetation so far advanced that cambium is beginning to form, or at least ready to form, so that bleeding will scarcely occur, or will cease soon after the operation has been performed. It is not that the bleeding in itself defeats the operation, unless it should be very long continued as well as very profuse, but because while it continues no granulations for uniting with the scion will put forth. It is true that continued bleeding will either prevent or destroy the callosity of the scion. Therefore I have said the action of each must be ready to meet the other. The stock must be active, and the scion, although kept back in a cool place, must at least be excitable; and the shock of transfer to a growing temperature must not be great. One bud is enough for each scion; and if the stock is pretty large, or an inch or more in diameter, two may be used.

The soil should be removed to sufficient depth to enable the operator to cut the stock below the collar and surface roots, if such have been suffered to form, so that in the first place the difficulty from the formation of shoots from the stock will be chiefly avoided, which is important, as the disposition to it will be very active, causing the failure of the operation. In the second place, it should be so low that the graft may send out its own roots, and thus insure permanence to the new vine, which will otherwise be of doubtful duration. Much more accuracy of fitting is required than for the apple or pear, and the usual injunction to have a sharp knife skillfully used is here particularly in place.

The work should be so well done that tying will not be required for the ap-tation of the parts, and that there shall be no springing apart after the ligature (which should be of bass) has decayed; still the tying should be stringently done, and so as to remain in full force for several weeks, as the union will not take place without strong and continued pressure. Under some circumstances, a young, healthy, well-planted vineyard may be advantageously converted into one of another variety, and one year of time gained by the operation; but plants on their own roots would be far preferable; and although it is one of the oldest operations that is accurately described by writers on the vine, it is but little resorted to by skillful vineyardists, not having been found advantageous.

The utmost advantage promised is small compared with that certainty obtainable on trees like the Apple and Pear, which require a long period to bring them into full heading. A thrifty Apple tree of twenty or thirty years' age, of undesirable variety, may, by grafting, be transformed into one of the kind desired within six years, and the new head, by this time, be able to bear a half crop, or from two to four barrels. A young tree from the nursery would require more than twice this time. The old tree would almost immediately give some good fruit, better in quality than could be obtained from a young tree under five years at least. A well-planted vine, under good treatment, will give good specimens the second year, or even the first, and a delightful crop the third. From the fourth to the sixth, according to the system adopted, it may become well established and in full bearing, under such favorable circumstances of planting and culture as the greatest amount of care and expenditure could not give to an old vine, but without which, if all else has been successful, its produce will be unsatisfactory.