As I gave you last year an account of my experiments with the new roots, and as I have since experimented further, I thought you and your readers might be pleased to know the results.

This last spring I divided my stock of roots into nearly 600 sets - most of which were very small and weak, owing to the division being pushed a little too far to increase the number. Most of these sets were planted one foot apart, each way, in a plot of ground dug three spades deep the previous fall, and with well-rotted manure laid in the trenches. At the time of planting the earth was only loosened up one spade deep. Time, 23d of March.

The balance of the sets were planted in ground dug equally deep at the time of planting, but with no manure. The result is about as follows: average weight from each set, about one pound and a quarter, mostly in single roots of that weight, but sometimes two or three roots; - the product from the plot not manured being the best! Many of those on the manured part never struck below the first layer of manure, but grew clubby, or in bunches, like potatoes. The average depth to which those penetrated which seemed to grow naturally, was two feet three inches. From this any one can calculate the product per acre.

In regard to the quality, I can only say that I prefer it to the potato, or any other similar vegetable, and should always grow it if only as a luxury.

The sets, as before remarked, were very small, and probably on that account were later in starting, and grew afterwards less vigorously; excepting a few of the larger ones, they scarcely appeared above ground till the first week in June, and some not till July.

As an experiment, one whole root was planted, which weighed one pound, and measured twenty-three inches long. It was stuck upright in the level ground, and the earth then heaped around it till covered, making a conical hill. This one started to grow at once, and by the second week in April had thrown up a vigorous shoot a foot high. A pole twenty feet high was placed in the hill, up which it began at once to climb, and by the end of July reached the top, and soon fell over, and matted together in a thick mass of leaves and runners. In August, it was covered with blossoms, in the axils of the leaves, and I hoped for seed. In place of seed, however, the blossoms were succeeded by small tubers, about the size of a large marrowfat pea. I gathered over 500 of these, and lost probably two or three hundred more, from this one plant.

On digging this root up in the fall, I found proof positive that the Dios-corea does not live, and continue to grow, more than one season. The old root was dead and withered, but from it had grown quite a bunch of other roots, weighing altogether over four pounds.

None of the others, from the small sets, bloomed at all, but produced abundance of tubers in the axils, though nothing like to the whole root. A few special manures were tried, but none of them with marked effect except wood ashes. The row to which this was applied was most certainly the best.

The result has shown me that if we plant sets they must have some bulk, and that the best part of the root to plant again is the thin end, especially if it have the very top, from which the growth begins at once. The small tubers, from the axils, are perhaps even better to plant. We can, therefore, consume the whole of the roots, excepting the thin top ends, which make good sets, and thus have an equal number of seta the next year again. And besides this, each plant will produce from ten to twenty tubers for sets, - or, as in the case of my large one, - even hundreds of them, each one of which will serve as a set again. In point of propagating power, therefore, the Dioscorea is all we could wish. .

I have heard of results equal to ten to twelve pounds to the plant, and of roots weighing from five to twelve pounds or more, but I have not seen any of these. And here let me remark, Mr. Editor, that the Dioscorea is in no way indebted to its friends and introducers, so far as I have seen, for any progress it may have made. I can find plenty of reported results from these men, which look very encouraging, but no details of the process by which said results were arrived at. The gentleman who averaged his twelve pounds to the plant, says it was done by ordinary cultivation. This, however, is very indefinite. If he reads the HorticuLturist, I should be glad if he would inform me, and other readers, what he means by ordinary cultivation. What kind of soil did ho plant in? Did he manure? and if so, with what? . What distance did he plant apart? What kind of sets did he use, and what time did he plant? There must have been something very different in his treatment, or soil, from mine, to produce such different results, and I should like to know in what that difference lies.

Gentlemen with the large roots, let us hear from you how it was done, circumstantially!

I am much pleased with the Dioscorea Batata, and are very desirous of seeing it succeed. Its excellent quality, beautiful appearance when cooked, and perfect hardihood and freedom from disease, speak strongly in its favor; but it is certain that, at present, its cultivation is not so successful, generally, as could be wished, although it possibly may become so, and I sincerely trust it will.

In-conclusion, Mr. Editor, let me, through your columns, plead so far in its favor as to recommend further experiments, in different-ways,"and in various localities; and let them be duly set forth, in such a way that we can see the causes of success or failure. Tor the purpose of aiding in this work I enclose you a number of the tubers, which I shall be glad if you will distribute, in small parcels of a' dozen or so, to different points,' among those of your correspondents who might not otherwise get them, and who will carefully and honestly experiment with them, so that we may known the result next year. - [We shall be most happy to do so. - ED].

This much I can advise: plant as early as possible, in deeply dug, light soil; keep free from weeds, and let them grow till the frost kills the vines. Possibly further south, where the season is longer, they may do much better than with us. But mind, when, digging them up, to reach the bottom of the root! You may have to go three Feet.

The Dioscorea Batatas #1

The result of my fourth year's experience with the Dioscorea batatas is, that I am satisfied it may be made a profitable and desirable article of cultivation, at least for the garden.

On deeply dug grounds, with a medium supply of well-rotted stable manure, I have produced roots weighing six pounds, from one plant, and I think they may be made to average five pounds. Some of mine were planted one foot apart each way, and others only six inches apart one way by a foot the other. On the same soil I observed no difference in the product, but, on the contrary, I think those at six inches were the best.

I decidedly think that the plant was much weakened when we first had it, constitutionally, by having been so much subdivided to increase the quantity for sale. The largest roots I could raise at first were very small compared with those I can raise now, and it certainly has improved each year, as the part planted has been larger and better developed.

The number of axillary tubers has also increased, and they, too, have been larger. In fact, the number produced of these tubers is enormous. They cover the ground, and thousands have to be dug in, or left on the surface. They will, however, remain in the ground all winter and come up themselves quite thick in the spring. These tubers will form good roots. when planted the following year, but not such large ones as those from other roots. The true plan seems to me to be this with them: To plant them quite thick, almost like seed, the following year after they are produced, and let them make small roots, which plant again the next year, say six inches by twelve, and they will then form fine roots of four to six pounds each.

When roots are planted it is best to lay them along the ground, horizontally, and just cover them over - at least mine did best that way. Next to whole roots, it is best to plant the thin ends of the largest roots, which are not good to cook.

1 should perhaps remark here, that the product of every plant is not one root, but often two or three.

The larger the root is that is planted, the larger the product will be as a general rule. The planted root does not grow, nor does it rot away, but only shrinks up, and hardens. The earliest start and the best growth are made from the top of the root, on the tip end of the thin part.

It is now demonstrated that this root is perfectly hardy, even in very severe climates, and it will also take care of itself. Any part left in the ground will produce other roots the next year, and the little tubers formed above ground will do the same. In fact, numbers of these will strike and make roots as large as the little finger, by fall.

This root may, therefore, be planted on the western prairies, and all along the various overland routes to California. In all those plains and valleys, and even on the mountain slopes, I feel confident it would soon multiply, if once planted; so that emigrants and others, who have to traverse those now foodless regions, could always depend upon it as a means of subsistence.

The importance of this, it seems to me, can scarcely be overrated, and I trust this brief allusion will call attention to it. The Federal government should see to this, and have the Dioscorea planted at the various military stations, and along the routes which the troops traverse. A single quart of the little tubers would start the plant over hundreds of miles, and then, as I before observed, it would take care of itself. Even on sandy plains, I have no doubt but it would attain at least an eatable size.

It would give me great pleasure to contribute my share of the tubers for this purpose, from my own stock, if any one will do the work.

Doubtless there are other wild regions in our country where a similar experiment could be tried, and if any gentleman feels desirous of trying it, I will send him the tubers with pleasure.

Those who wish to trace these experiments from the beginning, will find my previous articles in the back volumes of the Horticulturist, and those in the city who would like to see the roots - as seeing is believing - will find specimens at Mr. Elliot's seed store, in John St.

[Dr. Hollick deserves much credit for the persistent manner in which he has carried out his experiments with the greatly abused Dioscorea. It is only by such experiments that its value, whatever it may be, can become fully known. We have never believed that it was destined to supersede the common Potato, but supposed, notwithstanding, that it might have some useful properties. There is one thing at least about it which makes us wish that it might be introduced into every garden, and the owner compelled to dig it out clean: the ground would thus get a " stirring up" greatly beneficial to it,;and which, in nine cases out of ten, it would not get in any other way. Dr. Hollick's suggestion, that the Dioscorea should be planted along our military routes, might very well be taken into consideration by our government; though we can hardly hope for action on suck a subject in that quarter. - Ed].