The American Agriculturist. p 277 (1846)

In autumn, soon after the appearance of the first heavy frosts, let the potato balls or apples be gathered, macerated in water, the seeds separated from the pulp, and placed in some convenient place in the shade, to dry; after which they may be packed up in an air-tight box or bottle, and kept until required for use. As few of the early sorts produce blossoms, in order to produce seeds from them, deprive the plant of its tubers as they appear, and keep the runners from which they proceed above ground, by not earthing up the plant, and blossoms and seeds will soon appear. About the first of March, let them be sown in a hot-bed, in lines six inches apart, a quarter of an inch deep, and very thin. When water is necessary, sprinkle it between the lines, but avoid wetting the plants, that would injure them, taking care to give them a little fresh air before they are watered. As the plants increase in size, rich earth carefully put between the lines will add fresh vigor to them; but the tops of the plants must not be covered by the mouldings, which should occasionally be repeated until they are fit for transplanting. To prepare them for this, about the first of May, they must be plentifully refreshed with air; and, two hours before removing them, they must be copiously watered all over, and the glasses covered with mats, to prevent the sun, if shining at the time, from scorching the plants. Let each plant be taken up carefully, with a ball of earth attached to it, and plant them in trenches, after the manner of cultivating celery, only with this difference, the distance from plant to plant, in the lines, must be eighteen inches; and if the sun should be shining out strong at the time of planting, a flower-pot or any other convenient article may be placed over each, to prevent flagging; for, with all care exercised in taking them up, a good many of the fibres will be broken. After the plants have established themselves, remove the pot, and earth up occasionally, as long as the space between them will admit of it. The best manure employed in the operation is a mixture of fine turf and rotten horse-dung.

In plants produced from the seeds of the same ball, no two stems will, in all respects, possess the same qualities; yet, many of the tubers will have so near a resemblance to each other, that, when they are mixed together, they cannot be distinguished by the eye, though it may happen that one variety will be four times as prolific as the other, or may be much better in other respects. The tubers raised from the seeds of the same ball, are also prodigiously diversified in regard to color, being black, red, white, green, yellow, pink, &c.; to shape, as round, knobbed, and varied in all proportions; to size, some of them being no larger the first year than peas, while others exceed the size of a pullet's egg; to earliness, some of them completing their growth in July, while others will not put forth their blossoms before October; to productiveness, some yielding more than two hundred, while others will give only three or four; to spreading under ground, some running out to a great distance, others growing quite near to the stem, some descending deep into the earth, while others will rise to the surface; to quality, some being tough and watery, some dry and mealy, some very pleasing to the taste, and others will not be palatable at all; and as to stems, some will carry a single stalk, like a rod, others an immense profusion of them, some being very luxurious, while others will be extremely dwarfish. In short, what is remarkable, no sort of connection will be found to exist between any two peculiarities. Few plants which may resemble each other above ground, will often be found extremely dissimilar below the surface; while two tubers that apparently resemble each other, will sometimes be so different in quality, when tried for eating, that one will perhaps be among the best, and the other among the worst of the parcel. Hence the benefit that may be derived by a cautious selection from seedlings is obvious, as well as the evil consequences that may accompany a careless procedure in this respect. B.