The editorial article in the last number of the Horticulturist, on the "New Method of Constructing Vineries," afforded me much gratification. I esteem it a high compliment to find my plan of inside borders commended by the acute and discriminating conductor of this journal; and I am pleased to learn that borders, embodying the leading feature of my plan, have been proved, by years of trial, practically successful, and in many important respects a great improvement upon the common borders. I first constructed borders upon the plan in question about one year ago, and when I published my description of the "inside, detached, and divided border," I supposed that I was the first, either in England or America, to adopt this improvement. When I was in England last winter, I described my plan to several of the leading grape-growers in the first establishments in that country, and all acknowledged that it was new and promised good results. Neither the " Book of the Garden," by Mackintosh, nor any other English work or journal, has, to my knowledge, described or suggested an inside divided vine border, detached from the front wall, and drained and ventilated as I proposed.

But it seems that you, Mr. Editor, penetrated this field of improvement eleven years or more ago, and constructed a border embracing the leading features and principles of my plan ; I cheerfully yield to you the credit due to your ingenuity, originality, and judgment, and am right glad that I have found so able and intelligent an ally in the advocacy of the new border.

With your permission, I will state briefly wherein I think my inside border, detached from the front wall by an air chamber four inches wide, is superior to a border resting against a front wall, even if made follow so as to contain a body of air. In the first place, it is cheaper than a wall four or five feet thick, made hollow. My front wall is only nine inches thick, and the front wall of my border is only four inches. Secondly, any wall, even if made hollow, in very cold weather conducts heat away from the border. But chiefly I prefer the detached border because the open air chamber between the front wall and the border furnishes a passage through which the air of the house may be carried down front, and (by means of proper tubes or flues) entirely under the border. My object is to keep the whole border, at all times, as near as possible of the same temperature throughout (top and bottom) as the atmosphere of the house. It is true that the under side of the border and the air tubes will always be a little cooler than the house, but this only serves to condense the moisture in the air, and hence a current passing through these tubes must always become highly charged with humidity.

This new border, entirely inside the house, detached from it, divided into sections or huge pots, and thoroughly ventilated on the sides and underneath, and extra drained, is now under full trial in several houses besides my own, near Philadelphia, and we shall soon find all the objections to it, if there be any.

The method of cultivating the vine, described in my recent work on the Grape, viz., the single-stem system, growing a cane one year and fruiting it the next, and then cutting it down and growing a new cane before fruiting again, I think will be found a plan well suited to all kinds of culture, in doors and out, but especially to the inside and divided border. The plan mentioned by the editor of the HORTICULTURIST, of growing a new shoot from a grape root while fruiting a cane from the same root, (practised also by the German vine-growers in Ohio,) I do not think will ever meet with the most perfect success. You can not easily grow wood and fruit at the same time. Either the fruit or the new cane must suffer. This is my decided opinion. But let the profession test the matter and decide.

There is one subject connected with the management of vineries, not noticed in my work on grape culture, upon which I feel like saying a word, and that is, the prevention of mildew. I am quite convinced that a comparatively shallow, not very rich, inside border, well ventilated and well drained, will do much towards keeping the vines in forcing-houses, and cold-vineries, in a healthy, hardy condition, so that they will be better able to resist mildew, than they are under the old system of deep, over-rich, sodden borders, partly outside. But there are still other means of preventing mildew which I desire to notice.

What are the chief direct causes of mildew on the Grape in the forcing-house? In my opinion, they are, excessive moisture with deficient light and heat, or excessive dryness with light and heat. The chief requisites for successful grape growing, after you get healthy plants into a proper border, are, 1st, light; 2d, heat; 3d, moisture; 4th, air: upon the judicious management of these four great agents the whole result depends. A high degree of heat in a very dry, ill-ventilated house, even with light, will produce mildew. Cold, damp air, with light or without it, will have the same effect as hot, dry air. In the absence of sunlight, the tendency to mildew is always greater than in bright, clear weather, no matter what the other circumstances may be. Excess of humidity in a cold, dark, damp day is almost sure to produce mildew. The right management of the moisture of a house, in my opinion, is of far more consequence, and far more difficult, than that of air. It is astonishing how much heat the vine will bear, without injury, if you have plenty of moisture, plenty of light, and a little fresh air. With the condition just named, no matter how hot the house may be, if you don't boil the leaves, no mildew will be produced.

When there is but little clear sun-light, the heat and humidity of the house tend rapidly to produce mildew. In a damp, warm, cloudy day, with little sun-light, and no wind, there is no danger in "airing freely." There are such days, when it would do no harm to remove all the sash from a hothouse, while warm, genial showers are falling, and let the • vines and border receive a copious natural watering. But free ventilation is not so much needed in clear, light, brilliant days, as is generally supposed. On such days, if you have plenty of moisture, four inches of air, equally applied, along the top of each side of a span-roofed house, is amply sufficient. As I have said before, no matter what the heat may be, that of 212°, when you have got abundance of moisture and plenty of light, in a clear, brilliant day, and but little air is needed. When the atmosphere is charged with humidity in a very warm, cloudy, muggy day, then beware of excessive humidity in the house, without free ventilation. So, also, excessive humidity, in cold, dark, damp weather, is almost sure to create mildew.

I recommend, as a preventive of mildew, to pay particular attention to these facts, and especially to the management of Moisture. To this end, I place in my vineries large shallow Evaporating Troughs, sixteen or eighteen inches wide and four inches deep, running the whole length of the border, and resting upon it. These troughs are so contrived that the water can be pumped into them and let off at pleasure. In hot, light, dry, clear weather, these troughs are kept constantly filled with water, and the evaporation from such a surface of shallow water is immense, and serves to keep up an even and healthful degree of humidity without constantly sprinkling and syringing the house with the temperature at 100°; the evaporation from the troughs is so great that there is very little necessity for syringing, except to cleanse the foliage of the vines, and thus a vast saving of labor is effected at small expense. When the weather is cloudy, damp, and cold, then the water may be let off from the troughs, as a dryer atmosphere will be required to prevent mildew; and this is very readily done, returning the water to the cistern for future use.

I think if gardeners will try these large evaporating troughs, for producing humidity in forcing-houses and cold-vineries, they wilt be highly pleased with their effect Remember the principle, that hot, dry air will produce mildew as effectually as cold, damp air, and ventilation without humidity will not save you. If you have light, heat, and plenty of humidity, the vines will thrive in very little air, and will not mildew.

[We have to thank Mr. Bright for his excellent article on a subject so interesting to all grape-growers. We endorse his plan of inside borders cheerfully and confidently, because many years' experience has convinced us that its decided advantages over the old system can hardly be over-estimated. There can be no impropriety in stating our belief that we were the first to introduce the subject and test its value; we had never seen a line on the subject when we wrote our first article, which was several years after we had fully tested the plan. The reasoning which led us to adopt the plan was so natural that we felt no surprise that somebody else had arrived at the same conclusions. When, therefore, we saw Mr. Bright's article in the February number of the Gardener's Monthly, we did not hesitate to give his plan a full and cordial endorsement. We have since received his work, which we notice elsewhere. We shall now briefly notice two or three points in Mr. B.'s article; and first, we must candidly own that his detached inside wall is more perfect than our single hollow wall. In theory, a hollow wall is a perfect non-conductor; in practice, it is several removes from that condition; and that is just the difference between the two.

We have never seen a mason who could build a perfect hollow wall, though all profess their ability to do so. When such a man can be found, a wall need not necessarily be more than fifteen inches thick. We mentioned the case of one cane being fruited the full length of the rafter, at the same time that another was laid in for fruiting the next season, to show the vigor of vines eight years old in a narrow inside border. Though far from being perfect, it is a great advance upon the old spur system. M. B.'s plan, of giving the whole energies of the vine to the production of either fruit or wood, will, undoubtedly, yield far more satisfactory results.

There are three other points alluded to by Mr. B., viz., light, moisture, and heat, which are very imperfectly understood, but which are of peculiar significance in grape-culture. We hope his remarks on these points will be read attentively. We have elsewhere stated, that with a proper degree of light and moisture, no evil will result if the thermometer should rise to 175°; and Mr. Bright considers himself safe within 212°. We will here lay down the proposition, that, under proper conditions, the thermometer may be allowed to range, during the day, from 100° to 115° with decided benefit. What those conditions are, we shall explain fully on another occasion. In the mean time let our readers examine the proposition carefully, and controvert it if they can. We hope this first contribution from Mr. Bright will by no means be his last. - Ed].