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upon humble food, with gratitude; which will make vigorous foray upon a well-ripened cluster of even the Concord grape, without wiping the tongue around critically in search of missing flavors. There is a wise saying of an old Latinist, Nil sapiential odiosius acumine nimio (which every forward school-girl in tilting hoops can translate).

Again: I doubt very much if the finest flavored fruits can be grown as easily as the grosser tasting ones. I am quite aware that this dictum may start an angry buzz about my ears; but a good angry buzz in the matter of fruit discussion is often a very helpful thing.

Finest flavors seem to me to cost the finest labor, whether in fruit or speeches or poems or lives. Good things are aptest to come only by great care and task-work, no matter through whom or through what they come. Take the Delaware grape, for instance, whose flavor is, I think, admitted by all to be equal if not superior to that of any of our out-of-door grapes; yet only extreme care will give it fair size. Its buds are specially reluctant to grow under any of the ordinary means of propagation; it demands assiduous and delicate handling; it invites the thrips and all manner of vinedisorders, just as a delicate though promising child invites the whole turrieulum of child diseases. Again: take the Iona, whose rare flavor and signal beauty no one who has ever seen and tasted it can dispute ; yet the ordinary hap-hazard cultivator will very likely fail with it. It has grown up and developed under the best of nursing. It is offered to the public by one who does not believe in poor culture, scarcely in moderately good culture, but only in the best; and, with the best, it is a most admirable grape. But what shall we do with our friends Seth and Nathan, who do not know what first-class culture is? Shall we commend to them what will very likely perish under their hands?

In the pear line, it is quite possible, that with great nicety of treatment, both in garden-culture and in the ripening process (which last counts for a great deal), a higher and finer flavor may be given to the Beurr6 Diel, or the Flemish Beauty, or the Beurre' d'Anjou, or even the Duchess, than belongs ordinarily to the Bartlett. But put the Bartlett in comparison with either under fair average treatment, and upon ordinary garden lands, and I think two luscious Bartletts will present themselves to one of either of the other names. Now, it is quite possible that the man who does not practise the average hap-hazard culture should sneer at it, and refuse to recognize hap-hazard culture as any culture at all; but he must recognize it. It will never do for him to ignore positive facts, — such as lack of general nicety in culture, and lack of assiduous watchfulness. There are a vast many men in the world who are not watchful and painstaking in fruit-culture, who yet love fruits, and will grow them for themselves; just as there are a vast many men who are not critics or dilettanti, who will read average poems, and buy average pictures.

And why do I write in this strain? Is it to encourage mediocrity? Is it to disparage the efforts of advanced pomologists? Is it to make a plea for popular taste, and against cultivated taste? Not at all. It is simply to make clear the proper distinction between the two, and to secure its appropriate recognition.

This recognition once made, and the advisory horticultural committees could tell us more justly what is suited to common culture, and what to special culture. I plead only for the infiltration of the learned societies' reports with a little more of common sense, and an adaptation of their advice to the masses. Donald G. Mitchell.

Edgewood.

ATMOSPHERIC CHANGES.

Every one knows that our climate must be ranked among those termed excessive; i.e., subject to great diurnal fluctuations, and a wide annual range of temperature. These unpleasant changes, characteristic of the whole area excepting parts of the Pacific coast, are dependent on natural causes, and, of course, entirely beyond our control. The wide extent of land in high latitudes condemned by cold to perpetual desolation, and the absence of lofty mountain-ranges running east and west, render us liable at all seasons to violent and frigid winds from the north; while, on the other hand, we derive little benefit from the mitigating influences of the Gulf Stream, from the fact that the polar current flows between it and our eastern coast, and that the prevailing winds are from the west.

These points of climatology have been often discussed, and are well understood; indeed, they are impressed upon us by monthly experience. But there are other atmospheric changes of vastly more importance to the horticulturist, as influencing more directly the results of his labors. We refer to the rapid and often excessive fluctuations in the amount of aqueous vapor contained in the atmosphere; that change from dampness to dryness, or vice versa, so perceptible to the feelings, and accurately indicated by the wet-bulb thermometer. These fluctuations frequently occur during midsummer, and, with their concomitant phenomena, exert an injurious influence on vegetation; checking growth, and rendering plants liable to the attacks of disease. How these results are accomplished, we shall endeavor to explain farther on.

There is in "The Report of the Department of Agriculture" for 1865, quite recently published, a very instructive and important article headed "Observations on Atmospheric Humidity," by J. S. Lippincott of Haddonfield, N.J. Here we have these questions thoroughly discussed and scientifically explained, and various means suggested for the partial protection of growing plants from the results of sudden atmospheric changes. It is a paper which should be read and pondered by all who feel an interest in the fruits of the earth, whether they are the possessors of extensive plantations, or of only a few highly-prized trees and vines. It is principally in the hope of calling increased attention to this important subject, and with the purpose of suggesting a careful perusal of Mr. Lippincott's paper to the readers of this Magazine, that I have written these few notes.

From the narratives of travellers, and from meteorological observations, it has long been known that certain regions are subject to great depressions of temperature after sunset ; and that this refrigeration arrives at its maximum a little before sunrise, when the cold is often excessive (sufficient even for the formation of ice), though at noon of the same day the heat may be intense. This peculiarity of climate is especially developed in parts of the Sahara, and of what is called the "Great American Desert." It was also known, that, in all regions so characterized, a very dry atmosphere prevailed. Although generally accepted as a fact, that, the dryer the air of any country, the colder were its nights, this phenomenon remained unexplained until the laws governing it were discovered by John Tyndall, F.R.S., and demonstrated in the clearest manner in his well-known work "On Heat

VOL. I. 28

considered as a Mode of Motion." From long-continued and delicate experiments, Prof. Tyndall arrives at the conclusion, that aqueous vapor is opaque to the rays of heat of low intensity; in other words, that the presence of a considerable amount of moisture in the air prevents the radiation into space of heat from the soil and plants of that locality, and consequently a low night-temperature: but if, by the action of drying winds or otherwise, the proportion of aqueous vapor in the air be much reduced, the barriers to radiation are removed, and considerable nocturnal refrigeration follows. "The removal, for a single summer night, of the aqueous vapor from the atmosphere that covers England, would be attended by the destruction of every plant which a freezing temperature would kill." In the paper cited, Mr. Lippincott gives at considerable length the results of personal observations made in Camden County, N.J., during 1864 and 1865, in which there are many notable instances of a low degree of atmospheric humidity followed by excessive cold, in accordance with the theory of Prof. Tyndall. "On the 2 2d of July, at two, P.m., the force of vapor, or pressure, in inches on the barometer, was but .188; which is lower than we have ever observed it during summer and autumn, and lower than is sometimes noticed even at the freezing-point." On the morning of July 23, the temperature was but "460 at six feet above the soil; a narrow escape from frost."

It may now be asked in what manner these fluctuations in the humidity of the atmosphere concern the horticulturist, and whether it is in his power to protect his plants from the evils following in their train. These questions are discussed at length in Mr. Lippincott's paper. He mentions that the first appearance of mildew and rot in vines almost immediately followed the low morning temperatures consequent on the diminution of the quantity of aqueous vapor in the atmosphere of the locality.*

Why these sudden changes should cause mildew in the vine (and perhaps many other plant-diseases), may, I think, be thus explained. In a

• This agrees entirely with my own observations, although rny experience with mildew has been limited to a few spots on odd leaves ; the close vicinity of sea-water in nearly all directions preventing those sudden changes so injurious to the vine. In the present season, 1866, my vines were entirely healthy during the very hot and rainy weather of July and the early part of August: but with the first low morning temperatures, about Aug. 9, a few spots of mildew appeared; and, before Aug. 17, it had largely increased, and rot was discovered in a few clusters. Some of the worst cases were sulphured, and the disease checked. The last three weeks of August were cold, damp, and unfavorable.

plant growing under favorable conditions, both root and leaf action are well balanced, and regulate one another. Change these conditions, and functional disturbance is soon manifest. An instance of this is seen in the bad success attending plant-culture in the rooms of dwelling-houses. The air is too dry, and exhalation from the leaves is not compensated by absorption at the root. An extra supply of water does not remedy the evil; for the roots are not capable of pumping up the amount required. In short, the equilibrium necessary to health has been disturbed, and the plant languishes. In the case of our vines, we will suppose that a warm, moist atmosphere has excited the plant to vigorous growth. Suddenly the amount of moisture in the atmosphere is largely reduced; excessive reduction of temperature follows, and the leaves of our vine find themselves surrounded by cold, dry air: but, at the same time, the conditions at the roots remain unchanged; these are surrounded by moist earth at a temperature perhaps thirty degrees higher than that of the air. The conditions of healthy growth have now been reversed, the. delicate tissues of the leaves and fruit become disorganized, and the floating spores of mildew find speedy opportunities for their ravages. .

As a remedy for these evils, the planting of belts of trees is suggested as barriers to the sweep of drying winds, and as condensers and retainers of moisture; and also the use of a peculiar covered trellis, described and figured by William Saunders, Superintendent of the Public Garden at Washington, in the Agricultural Report for 1861.*

With regard to tree-planting, we hope the subject will be agitated until practical results follow. By the wholesale destruction of the forests, we, or rather our ancestors, have changed essentially the climate of the country, and for the worse. The disastrous effects of our improvidence are now very apparent. Prolonged droughts, and an extreme range of temperature, are not uncommon in all parts of the country. Many fruits, once easily produced, now fail, or are uncertain, with us. Many years ago, when the country was thinly settled, the orange was a sure crop along the coast, in Georgia, Alabama, Mississippi, and other States; and the trees attained

• Mr. Saunders has had this trellis in use for many years, and has always found it effectual. It is very simple in construction, and well worthy of a trial; and, moreover, we can now pretty well understand why it should tend to preserve the health of the vines.

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