Man and Nature - Part 42
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Part 42

No. 7 (page 60, _first note_). At Pie di Mulera, at the outlet of the Val Anzasca, near the princ.i.p.al hotel, is a vine measuring thirty-one inches in circ.u.mference. The door of the chapter-hall in the cloister of the church of San Giovanni, at Saluzzo, is of vine wood, and the boards of which the panels were made could not have been less than ten inches wide. Statues and other objects of considerable dimensions, of vine wood, are mentioned by ancient writers.

No. 8 (page 63, _second note_). Cartier, A. D. 1535-'6, mentions "vines, great melons, cuc.u.mbers, gourds [courges], pease, beans of various colors, but not like ours," as common among the Indians of the banks of the St. Lawrence.--_Bref Recit_, etc., reprint. Paris, 1863, pp. 13, a; 14, b; 20, b; 31, a.

No. 8 (page 65, _second paragraph_). It may be considered very highly probable, if not certain, that the undiscriminating herbalists of the sixteenth century must have overlooked many plants native to this island. An English botanist, in an hour's visit to Aden, discovered several species of plants on rocks always reported, even by scientific travellers, as absolutely barren. But after all, it appears to be well established that the original flora of St. Helena was extremely limited, though now counting hundreds of species.

No. 9 (page 66, _first note_). Although the vine _genus_ is very catholic and cosmopolite in its habits, yet particular _varieties_ are extremely fastidious and exclusive in their requirements as to soil and climate. The stocks of many celebrated vineyards lose their peculiar qualities by transplantation, and the most famous wines are capable of production only in certain well-defined, and for the most part narrow districts. The Ionian vine which bears the little stoneless grape known in commerce as the Zante currant, has resisted almost all efforts to naturalize it elsewhere, and is scarcely grown except in two or three of the Ionian islands and in a narrow territory on the northern sh.o.r.es of the Morea.

No. 10 (page 68, _first note_). In most of the countries of Southern Europe, sheep and beeves are wintered upon the plains, but driven in the summer to mountain pastures at many days' distance from the homesteads of their owners. They transport seeds in their coats in both directions, and hence Alpine plants often shoot up at the foot of the mountains, the gra.s.ses of the plain on the borders of the glaciers; but in both cases, they usually fail to propagate themselves by ripening their seed. This explains the scattered tufts of common clover, with pale and flaccid blossoms, which are sometimes seen at heights exceeding 7,000 feet above the sea.

No. 11 (page 73, _last paragraph_). The poisonous wild parsnip, which is very common in New England, is popularly believed to be identical with the garden parsnip, and differenced only by conditions of growth, a richer soil depriving it, it is said, of its noxious properties. Many wild medicinal plants, such as pennyroyal for example, are so much less aromatic and powerful, when cultivated in gardens, than when self-sown on meagre soils, as to be hardly fit for use.

No. 12 (page 74, _second note_). See in Th.o.r.eau's _Excursions_, an interesting description of the wild apple-trees of Ma.s.sachusetts.

No. 13 (page 86, _first paragraph_). It is said at Courmayeur that a very few ibexes of a larger variety than those of the Cogne mountains, still linger about the Grande Jora.s.se.

No. 14 (page 92, _first note_). In Northern and Central Italy, one often sees hillocks crowned with grove-like plantations of small trees, much resembling large arbors. These serve to collect birds, which are entrapped in nets in great numbers. These plantations are called _ragnaje_, and the reader will find, in Bindi's edition of Davanzati, a very pleasant description of a ragnaja, though its authorship is not now ascribed to that eminent writer.

No. 15 (page 93, _second note_). The appearance of the dove-like grouse, _Tetrao paradoxus_, or _Syrrhaptes Pallasii_, in various parts of Europe, in 1859 and the following years, is a noticeable exception to the law of regularity which seems to govern the movements and determine the habitat of birds. The proper home of this bird is the steppes of Tartary, and it is not recorded to have been observed in Europe, or at least west of Russia, until the year abovementioned, when many flocks of twenty or thirty, and even a hundred individuals, were seen in Bohemia, Germany, Holland, Denmark, England, Ireland, and France. A considerable flock frequented the Frisian island of Bork.u.m for more than five months.

It was hoped they would breed and remain permanently in the island, but this expectation has been disappointed, and the steppe-grouse seems to have disappeared again altogether.

No. 16 (page 94, _note_). From an article by A. Esquiros, in the _Revue des Deux Mondes_ for Sept. 1, 1864, ent.i.tled, _La vie Anglaise_, p. 119, it appears that such occurrences as that stated in the note are not unfrequent on the British coast.

No. 17 (page 100, _first paragraph_). I cannot learn that caprification is now practised in Italy, but it is still in use in Greece.

No. 18 (page 112, _first note_). The recent great multiplication of vipers in some parts of France, is a singular and startling fact.

Toussenel, quoting from official doc.u.ments, states, that upon the offer of a reward of fifty centimes, or ten cents, a head, _twelve thousand_ vipers were brought to the prefect of a single department, and that in 1859 fifteen hundred snakes and twenty quarts of snakes' eggs were found under a farm-house hearthstone. The granary, the stables, the roof, the very beds swarmed with serpents, and the family were obliged to abandon its habitation. Dr. Viaugrandmarais, of Nantes, reported to the prefect of his department more than two hundred recent cases of viper bites, twenty-four of which proved fatal.--_Tristia_, p. 176 _et seqq._

No. 19 (page 121, _first note_). The Beduins are little given to the chase, and seldom make war on the game birds and quadrupeds of the desert. Hence the wild animals of Arabia are less timid than those of Europe. On one occasion, when I was encamped during a sand storm of some violence in Arabia Petraea, a wild pigeon took refuge in one of our tents which had not been blown down, and remained quietly perched on a boy in the midst of four or five persons, until the storm was over, and then took his departure, _insalutato hospite_.

No. 20 (page 122). It is possible that time may modify the habits of the fresh water fish of the North American States, and accommodate them to the now physical conditions of their native waters. Hence it may be hoped that nature, even unaided by art, will do something toward restoring the ancient plenty of our lakes and rivers. The decrease of our fresh water fish cannot be ascribed alone to exhaustion by fishing, for in the waters of the valleys and flanks of the Alps, which have been inhabited and fished ten times as long by a denser population, fish are still very abundant, and they thrive and multiply under circ.u.mstances where no American species could live at all. On the southern slope of those mountains, trout are caught in great numbers, in the swift streams which rush from the glaciers, and where the water is of icy coldness, and so turbid with particles of fine-ground rock, that you cannot see an inch below the surface. The glacier streams of Switzerland, however, are less abundant in fish.

No. 21 (page 131, _note_). Vaupell, though agreeing with other writers as to the injury done to the forest by most domestic animals--which he ill.u.s.trates in an interesting way in his posthumous work, _The Danish Woods_--thinks, nevertheless, that at the season when the mast is falling swine are rather useful than otherwise to forests of beech and oak, by treading into the ground and thus sowing beechnuts and acorns, and by destroying moles and mice.--_De Danske Skore_, p. 12.

No. 22 (page 135, _note_). The able authors of Humphreys and Abbot's most valuable Report on the Physics and Hydraulics of the Mississippi, conclude that the delta of that river began its encroachments on the Gulf of Mexico not more than 4,400 years ago, before which period they suppose the Mississippi to have been "a comparatively clear stream,"

conveying very little sediment to the sea. The present rate of advance of the delta is 262 feet a year, and there are reasons for thinking that the amount of deposit has long been approximately constant.--_Report_, pp. 435, 436.

The change in the character of the river must, if this opinion is well founded, be due to some geological revolution, or at least convulsion, and the hypothesis of the former existence of one or more great lakes in its upper valley, whose bottoms are occupied by the present prairie region, has been suggested. The sh.o.r.es of these supposed lakes have not, I believe, been traced, or even detected, and we cannot admit the truth of this hypothesis without supposing changes much more extensive than the mere bursting of the barrier which confined the waters.

No. 23 (page 143, _note_). See on this subject a paper by J. Jamin, in the _Revue des Deux Mondes_ for Sept. 15, 1864; and, on the effects of human industry on the atmosphere, an article in _Aus der Natur_, vol.

29, 1864, pp. 443, 449, 465 _et seqq._

No. 24 (page 159, _second paragraph_). All evergreens, even the broad-leaved trees, resist frosts of extraordinary severity better than the deciduous trees of the same climates. Is not this because the vital processes of trees of persistent foliage are less interrupted during winter than those of trees which annually shed their leaves, and therefore more organic heat is developed?

No. 25 (page 191, _first paragraph_). In discussing the influence of mountains on precipitation, meteorologists have generally treated the popular belief, that mountains "attract" to them clouds floating within a certain distance from them, as an ignorant prejudice, and they ascribe the appearance of clouds about high peaks solely to the condensation of the humidity of the air carried by atmospheric currents up the slopes of the mountain to a colder temperature. But if mountains do not really draw clouds and invisible vapors to them, they are an exception to the universal law of attraction. The attraction of the small Mount Shehallien was found sufficient to deflect from the perpendicular, by a measurable quant.i.ty, a plummet weighing but a few ounces. Why, then, should not greater ma.s.ses attract to them volumes of vapor weighing hundreds of tons, and floating freely in the atmosphere within moderate distances of the mountains?

No. 26 (page 198, _note_). elisee Redus ascribes the diminution of the ponds which border the dunes of Gascony to the absorption of their water by the trees which have been planted upon the sands.--_Revue des Deux Mondes_, 1 Aug., 1863, p. 694.

No. 27 (page 219, _note_). The waste of wood in European carpentry was formerly enormous, the beams of houses being both larger and more numerous than permanence or stability required. In examining the construction of the houses occupied by the eighty families which inhabit the village of Faucigny, in Savoy, in 1834, the forest inspector found that _fifty thousand_ trees had been employed in building them. The builders "seemed," says Hudry-Menos, "to have tried to solve the problem of piling upon the walls the largest quant.i.ty of timber possible without crushing them."--_Revue des Deux Mondes_, 1 June, 1864, p. 601.

No. 28 (page 231, _note_). In a remarkable pamphlet, to which I shall have occasion to refer more than once hereafter, ent.i.tled _Avant-projet pour la creation d'un sol fertile a la surface des Landes de Gascogne_, Duponchel argues with much force, that the fertilizing properties of river-slime are generally due much more to its mineral than to its vegetable const.i.tuents.

No. 29 (page 265, _note_). Even the denser silicious stones are penetrable by fluids and the coloring matter they contain, to such an extent that agates and other forms of silex may be artificially stained through their substance. This art was known to and practised by the ancient lapidaries, and it has been revived in recent times.

No. 30 (page 268). There is good reason for thinking that many of the earth and rock slides in the Alps occurred at an earlier period than the origin of the forest vegetation which, in later ages, covered the flanks of those mountains. See _Bericht uber die Untersuchung der Schweizerischen Hochgebirgswaldungen_. 1862. P. 61.

Where more recent slides have been again clothed with woods, the trees, shrubs, and smaller plants which spontaneously grow upon them are usually of different species from those observed upon soil displaced at remote periods. This difference is so marked that the site of a slide can often be recognized at a great distance by the general color of the foliage of its vegetation.

No. 31 (page 286, _note_). It should have been observed that the venomous principle of poisonous mushrooms is not decomposed and rendered innocent by the process described in the _note_. It is merely extracted by the acidulated or saline water employed for soaking the plants, and care should be taken that this water be thrown away out of the reach of mischief.

No. 32 (page 293, _note_). Gaudry estimates the ties employed in the railways of France at thirty millions, to supply which not less than two millions of large trees have been felled. These ties have been, upon the average, at least once renewed, and hence we must double the number of ties and of trees required to furnish them.--_Revue des Deux Mondes_, 15 July, 1863, p. 425.

No. 33 (page 294, _second paragraph of note_). After all, the present consumption of wood and timber for fuel and other domestic and rural purposes, in many parts of Europe, seems incredibly small to an American. In rural Switzerland, the whole supply of firewood, fuel for small smitheries, dairies, breweries, brick and lime kilns, distilleries, fences, furniture, tools, and even house building--exclusive of the small quant.i.ty derived from the tr.i.m.m.i.n.gs of fruit trees, grape vines and hedges, and from decayed fences and buildings--does not exceed an average of _two hundred and thirty cubic feet_, or less than two cords, a year per household. The average consumption of wood in New England for domestic fuel alone, is from five to ten times as much as Swiss families require for all the uses above enumerated. But the existing habitations of Switzerland are sufficient for a population which increases but slowly, and in the peasants' houses but a single room is usually heated. See _Bericht uber die Untersuchung der Schweiz. Hochgebirgswaldungen_, pp. 85-89.

No. 34 (page 304). Among more recent manuals may be mentioned: _Les etudes de Maitre Pierre._ Paris, 1864. 12mo; BAZELAIRE, _Traite de Rebois.e.m.e.nt_. 2d edition, Paris, 1864; and, in Italian, SIEMONI, _Manuale teorico-pratico d'arte Forestale_. Firenze, 1864. 8vo. A very important work has lately been published in France by Viscount de Courval, which is known to me only by a German translation published at Berlin, in 1864, under the t.i.tle, _Das Aufasten der Waldbaume_. The princ.i.p.al feature of De Courval's very successful system of sylviculture, is a mode of tr.i.m.m.i.n.g which compels the tree to develop the stem by reducing the lateral ramification. Beginning with young trees, the buds are rubbed off from the stems, and superfluous lateral shoots are pruned down to the trunk. When large trees are taken in hand, branches which can be spared, and whose removal is necessary to obtain a proper length of stem, are very smoothly cut off quite close to the trunk, and the exposed surface is _immediately_ brushed over with mineral-coal tar. When thus treated, it is said that the healing of the wound is perfect, and without any decay of the tree.

No. 35 (page 313). The most gorgeous autumnal coloring I have observed in the vegetation of Europe, has been in the valleys of the Durance and its tributaries in Dauphiny. I must admit that neither in variety nor in purity and brilliancy of tint, does this coloring fall much, if at all, short of that of the New England woods. But there is this difference: in Dauphiny, it is only in small shrubs that this rich painting is seen, while in North America the foliage of large trees is dyed in full splendor. Hence the American woodland has fewer broken lights and more of what painters call breadth of coloring. Besides this, the arrangement of the leaf.a.ge in large globular or conical ma.s.ses, affords a wider scale of light and shade, thus aiding now the gradation, now the contrast of tints, and gives the American October landscape a softer and more harmonious tone than marks the humble shrubbery of the forest hill-sides of Dauphiny.

Th.o.r.eau--who was not, like some very celebrated landscape critics of the present day, an outside spectator of the action and products of natural forces, but, in the old religious sense, an _observer_ of organic nature, living, more than almost any other descriptive writer, among and with her children--has a very eloquent paper on the "Autumnal Tints" of the New England landscape.--See his _Excursions_, pp. 215 _et seqq._

Few men have personally noticed so many facts in natural history accessible to unscientific observation as Th.o.r.eau, and yet he had never seen that very common and striking spectacle, the phosph.o.r.escence of decaying wood, until, in the latter years of his life, it caught his attention in a bivouac in the forests of Maine. He seems to have been more excited by this phenomenon than by any other described in his works. It must be a capacious eye that takes in all the visible facts in the history of the most familiar natural object.--_The Maine Woods_, p.

184.

"The luminous appearance of bodies projected against the sky adjacent to the rising" or setting sun, so well described in Professor Necker's Letter to Sir David Brewster, is, as Tyndall observes, "hardly ever seen by either guides or travellers, though it would seem, _prima facie_, that it must be of frequent occurrence." See TYNDALL, _Glaciers of the Alps_. Part I. Second ascent of Mont Blanc.

Judging from my own observation, however, I should much doubt whether this brilliant phenomenon can be so often seen in perfection as would be expected; for I have frequently sought it in vain at the foot of the Alps, under conditions apparently otherwise identical with those where, in the elevated Alpine valleys, it shows itself in the greatest splendor.

No. 36 (page 314). European poets, whose knowledge of the date palm is not founded on personal observation, often describe its trunk as not only slender, but particularly _straight_. Nothing can be farther from the truth. When the Orientals compare the form of a beautiful girl to the stem of the palm, they do not represent it as rigidly straight, but on the contrary as made up of graceful curves, which seem less like permanent outlines than like flowing motion. In a palm grove, the trunks, so far from standing planted upright like the candles of a chandelier, bend in a vast variety of curves, now leaning towards, now diverging from, now crossing, each other, and among a hundred you will hardly see two whose axes are parallel.

No. 37 (page 316, _first note_). Charles Martin ascribes the power of reproduction by shoots from the stump to the cedar of Mount Atlas, which appears to be identical with the cedar of Lebanon.--_Revue des Deux Mondes_, 15 July, 1864, p. 315.

No. 38 (page 332). In an interesting article on recent internal improvements in England, in the London Quarterly Review for January, 1858, it is related that in a single rock cutting on the Liverpool and Manchester railway, 480,000 cubic yards of stone were removed; that the earth excavated and removed in the construction of English railways up to that date, amounted to a hundred and fifty million cubic yards, and that at the Round Down Cliff, near Dover, a single blast of nineteen thousand pounds of powder blew down a thousand million tons of chalk, and covered fifteen acres of land with the fragments.

No. 39 (page 339). According to Reventlov, whose work is one of the best sources of information on the subject of diking-in tide-washed flats, _Salicornia herbacea_ appears as soon as the flat is raised high enough to be dry for three hours at ordinary ebb tide, or, in other words, where the ordinary flood covers it to a depth of not more than two feet.

At a flood depth of one foot, the _Salicornia_ dies and is succeeded by various sand plants. These are followed by _Poa distans_ and _Poa maritima_ as the ground is raised by further deposits, and these plants finally by common gra.s.ses. The _Salicornia_ is preceded by _confervae_, growing in deeper water, which spread over the bottom, and when covered by a fresh deposit of slime reappear above it, and thus vegetable and alluvial strata alternate until the flat is raised sufficiently high for the growth of _Salicornia_.--_Om Marskdannelsen paa Vestkysten af Hertugdommet Slesvig_, pp. 7, 8.

No. 40 (page 348, _note_). The drijftil employed for the ring dike of the Lake of Haarlem, was in part cut in sections fifty feet long by six or seven wide, and these were navigated like rafts to the spot where they were sunk to form the dike.--EMILE DE LAVELEYE, _Revue des Deux Mondes_, 15 Sept., 1863, p. 285.

No. 41 (page 352, _last paragraph_). See on the influence of the improvements in question on tidal and other marine currents, Staring, _De Bodem van Nederland_, I. p. 279.

Although the dikes of the Netherlands and the adjacent states have protected a considerable extent of coast from the encroachments of the sea, and have won a large tract of cultivable land from the dominion of the waters, it has been questioned whether a different method of accomplishing these objects might not have been adopted with advantage.

It has been suggested that a system of inland dikes and ca.n.a.ls, upon the principle of those which, as will be seen in a subsequent part of the chapter on the waters, have been so successfully employed in the Val di Chiana and in Egypt, might have elevated the low grounds above the ocean tides, by spreading over them the sediment brought down by the Rhine, the Maes, and the Scheld. If this process had been introduced in the Middle Ages and constantly pursued to our times, the superficial and coast geography, as well as the hydrography of the countries in question, would undoubtedly have presented an aspect very different from their present condition; and by combining the process with a system of maritime dikes, which would have been necessary, both to resist the advance of the sea and to retain the slime deposited by river overflows, it is possible that the territory of those states would have been as extensive as it now is, and, at the same time, more elevated by several feet. But it must be borne in mind that we do not know the proportions in which the marine deposits that form the polders have been derived from materials brought down by these rivers or from other more remote sources. Much of the river slime has no doubt been transported by marine currents quite beyond the reach of returning streams, and it is uncertain how far this loss has been balanced by earth washed by the sea from distant sh.o.r.es and let fall on the coasts of the Netherlands and other neighboring countries.

We know little or nothing of the quant.i.ty of solid matter brought down by the rivers of Western Europe in early ages, but, as the banks of those rivers are now generally better secured against wash and abrasion than in former centuries, the sediment transported by them must be less than at periods nearer the removal of the primitive forests of their valleys. Kloden states the quant.i.ty of sedimentary matter now annually brought down by the Rhine at Bonn to be sufficient only to cover a square English mile to the depth of a little more than a foot.--_Erdkunde_, I. p. 384.

No. 42 (page 358, _first paragraph_). Meteorological observations have been regularly recorded at Zwanenburg, near the north end of the Lake of Haarlem, for more than a century, and since 1845 a similar register has been kept at the Helder, forty or fifty miles farther north. In comparing these two series of observations, it is found that about the end of the year 1852, when the drawing off of the waters of the Lake of Haarlem was completed, and the preceding summer had dried the grounds laid bare so as greatly to reduce the evaporable surface, a change took place in the relative temperature of the two stations. Taking the mean of every successive period of five days from 1845 to 1852, the temperature at Zwanenburg was thirty-three hundredths of a centigrade degree _lower_ than at the Helder. Since the end of 1852, the thermometer at Zwanenburg has stood, from the 11th of April to the 20th of September inclusive, twenty-two hundredths of a degree _higher_ than at the Helder, but from the 14th of October to the 17th of March, it has averaged one-tenth of a degree _lower_ than its mean between the same dates before 1853.

There is no reasonable doubt that these differences are due to the draining of the lake. There has been less refrigeration from evaporation in summer, and the ground has absorbed more solar heat at the same period, while in the winter it has radiated more warmth then when it was covered with water. Doubtless the quant.i.ty of humidity contained in the atmosphere has also been affected by the same cause, but observations do not appear to have been made on that point. See KRECKE, _Het Klimaat van Nederland_, II. 64.