We last month published a description of this Dew Grape by Dr. Brincke. We have just received the following letter from Mr. Berckmans, which contains some interesting particulars in addition to those already published:

In the January number of this year, you mention the Mazatawny grape, and you ask if somebody can give you any information about that variety. I had supposed that some amateurs of Pennsylvania, acquainted with that fruit for the past three or four years, would have replied to your inquiry ; but as I find no answer to the question in your just received number of this month. I venture to give you the little information I possess, by one year's experience; I do it because I think it the duty of every amateur of fruits to make known, as soon as possible, - that is, as soon as anything certain and reliable can be stated, - any variety that can add something to our pomological luxuries.

I tasted the fruit last season for the first time, and, through the kindness of a Philadelphia friend, I received a young vine in the same year, (1859).

I will first tell you about the vine before I mention the fruit, as I had that vine under my observation for a long time before I knew anything about the grape.

The layer I received was planted on high ground, not rich, but well sub-soiled, and started fairly about the middle of March. All the summer it grew with great vigor, and at the end of the season I believe that the different vines from that single small layer measured in extent over 60 feet; indeed, it took hold of all things standing within six feet distance, and overshadowed everything with its broad and profuse foliage. I consider it equal in vigor to our best southern growers, if not superior. Another summer will no doubt develop its full power of vegetation, the vine just out the ground being now four inches in circumference, strong and sound as a wild vine.

The foliage is very large, the outlines showing a foreign origin, while its downy cover underneath bears the unmistakable stamp of the American family. It is evidently a Hybrid from the Malaga, and, as such, giving promise of hardiness and adaptedness to onr climate.

There can be no doubt that this excellent fruit will prove a first-rate grape for transportation. The Malaga grapes are sent all over Europe with perfect security. They are sold at exorbitant prices in St. Petersburgh, Russia, and are always kept, for a protracted season, in the best fruit stores of the large European cities.

I must think, and I am almost sure, that my vine is the first that has grown the other side of the so-called Southern division line; and I feel confident that I shall be able to test its merits fully in the coming season, when I shall also be able to send you the fruit as a test of its qualities and adaptedness for distant transportation.

I refer to my son for an accurate and technical description of leaves and fruit, as he has taken special notice of the growing vine and of the fruit sent to us in the latter part of September, 1859. He has deemed it worthy of large propagation, and I believe has potted every eye of the vines.

Bunches were received Sept. 38, 1859. Bunch medium, loose. Berries medium, oblong, greenish yellow, and transparent; have much water and some pulp; skin thin; flavor sweet, and partaking strongly of the Muscat grapes. Seeds large, and generally one in a berry. Its analogy with the Malaga le gros or jar grape of commerce, is very palpable, nearly the same fruit and same qualities for drying, as the berries will shrivel up, but will not rot. The wood is, however, very different, as its characters are unmistakably native. Yours, etc, L. E. Berckmans.

To the Editor of the Horticulturist:

Sir: - Upon reading the description and recommendation of Orchard Houses, by Mr. Rivers, in the June, July, and August numbers of the Horticulturist for 1859,1 felt a desire to attempt something of the kind for myself, although conscious of ignorance, and fearful that the production of fruit from trees grown in flower-pots would prove scarcely practicable in unskilled hands. Taking the estimate of cost, as given by Mr. Rivers, and Americanized by Mr. Smith, I proposed to a builder with whom I had previously had some dealings, to erect for me an Orchard House, of the moderate dimensions given as a standard, which he agreed to do at the estimated cost, except as to the posts, which I was to furnish, to make up for the greater cost of glass in this country. (I had supposed that glass of the kind required would be cheaper in this country than in England, but found the contrary to be the case).

I preferred the lean-to form, wishing to place the house against the south wall of a stable, which would afford important protection against the cold in winter and early spring. The arrangement of the building, and the composition of the borders, were, as nearly as possible, those recommended by Mr. Rivers; and about the first of November I procured the trees and vines, to the number of about thirty, (for a house thirty by twelve and a half feet,) not placing them in pots exactly, but principally in boxes and kegs, by the advice of a horticultural friend. After the thorough soaking prescribed by Mr. Rivers, I left the trees to themselves, as directed - not a leaf to be seen, of course. When the severe frosts came, I began to remember how much more inclement our climate is than that of England, and forthwith had the trees set close together, and well-covered with salt hay, by way of mulch. But thus far there has been absolutely no frost in the Orchard House; no cold or snow that we have yet had having brought the temperature down much below 40°. On the contrary, the thermometer there is so often above 60°, that I sometimes fear the trees will think it spring, and burst out prematurely into bud.

My object in mentioning this my first attempt, is, to ask information as to American experience of Orchard Houses, since, considering the differences of climate, English plans and successes are hardly satisfactory to beginners as unpractised as myself. If any of your subscribers, who have factually raised fine fruit on dwarf trees in an Orchard House, would kindly describe methods and results in your pages, it would bo a favor to me, and doubtless many others of your readers.

I am encouraged to ask this by the sudden and wide-spread celebrity into which the Orchard House has sprung of late. We meet it everywhere; and even the London Quarterly Review has thought it worth while to recommend to its readers, what it calls the raising of " fruit for the million,"at small cost of money or trouble.

It is, of course, more important in England to learn special modes of bringing delicate fruits to perfection, than in our country, where glowing suns do so much work for us with such success. But the experience of late years shows that the early warmth and late frosts of our springs, together with the premature frosts of early autumn, disappoint, in too many cases, our best endeavors and highest hopes. It is to remedy these evils that we want Orchard Houses; and if protection can be thus cheaply afforded, assuring us always of tome peaches fresh from the tree, some unstung apricots and nectarines, and a few well-grown figs, to say nothing of winter pears and sweet grapes, we may consider ourselves amply rewarded. But in truth this, like other horticultural attempts, brings with it its own reward, in health and pleasure.

Perth Amboy, N. J. Yours, Leafring.

[Can any of our readers give Leafring the desired information? We feel confident that the management of Orchard Houses in this country must be varied from that recommended by Rivers for England, and those building Orchard Houses would do well to bear this in mind. Leafring seems to have taken hold of the subject with so much intelligence and spirit, that we are fain to believe that he will bo among the first to give the information for which he himself now asks. We sincerely wish we could help him. We can give him suggestions, but we have nothing in the way of experience on this subject to offer him. - Ed].

Ed. of the Horticulturist: - In your March number there is a very interesting article on Heating Apparatus for Horticultural buildings. Short, practical, common-sense remarks of this kind have a great influence on the advancement of Horticulture. Presuming they are chiefly intended for amateurs and those without experience in such matters, great care should be taken by the authors not to be too sanguine until public opinion justifies presumption, and new inventions have stood the test of time. On that account I would invite you, as part of your editorial duties, to call upon all those who have had practical experience during the past winter, to state facts as to the working of the combined Saddle and Conical Boiler; and whether it has always been found what he claims it to be when compared with the improved conical boiler. I have myself in use a number 5 conical boiler, heating thoroughly little short of 900 feet of 4-inch pipe, which, for steady action, economy in fuel, and easy management, will be hard to beat Now let us hear from all others interested, by a general call, through your flourishing magazine, that we may be fully convinced which is the best.

Nobody.

["Nobody"' is right on the "boiler subject/ which the reader can take as a double entendre or not, as he pleases; at all events, let us now hear what " everybody" has to say. Being appealed to on the score of duty, we call upon our readers to " steam up," and put their boilers in order for a thorough test. The subject is a warm one, but we hope our friends will keep cool and give us an impartial record. Our remark last month referred to the old Cone Boiler, and not to the one figured, as we have had no opportunity of seeing that We mean, however, to examine them all. - Ed].

Detroit, March 12, 1860. Edit. Horticulturist: - My Grapery is 15 by 20 feet. In the illustration, No. 7 should be supports and braces. I have had several letters inquiring as to size of house, and would be obliged if you would give it for the information of those interested. A house, constructed after this plan, 30 feet in length, could be built for five dollars per running foot. This house answers very well, but I would prefer to have it a little higher, and would put a tier of glass - say 10 by 15 - under the plates upon each aide, and dispense with the glazing around the north end. Your suggestion of Kyanizing the timber is a good one. In Boston they Burnettize the timbers used in constructing horse railroads. They use spruce timber, and say, thus prepared, it will last fifty years. The February number of the Horticulturist was not received here until last week. I am very glad you design making it more practical; it will benefit a larger class, and I think increase the circulation. Respectfully yours, etc, A. C. Hubbard.

[We print Mr. Hubbard's letter for the benefit of those of our readers who desire information in regard to his plan of a greenhouse. We do not know why you got the February number so late. We have received a good many complaints from Detroit, and the magazine has been sent to many of our subscribers there three several times without having reached its destination. Can the postmaster at Detroit shed any light on this dark subject? - Ed. ]