Popular Science Monthly/Volume 4/January 1874/Miscellany
Physical Conditions of Inland Seas.—In the August number of the Contemporary Review is a paper of great interest by Dr. Carpenter, in which that scientist explains some curious phenomena of inland seas. It is well known that in the open ocean the depths are uniformly colder than near the surface, so that, while the surface-water in some cases approaches 80° Fahr., the temperature is near the freezing-point at depths of one or two miles. This appears to occur where the movement of water is unobstructed by inequalities of the ocean's bed. Where these are present, however, the temperature is more uniform throughout, as in the Sulu Sea, where the water is at 50° at the greatest depths, but in the contiguous but more open China Sea it is at 37° in deep soundings.
From the cause assigned, the inland seas show a uniformity of temperature as compared with the open oceans. While the surface-waters may be of equal temperature, the depths present great contrast. The Straits of Gibraltar are quite shallow, and a free interchange of waters between the Atlantic and the Mediterranean is impossible. From local causes there is frequently no current, or but a very slight one, either one way or the other. As a consequence of this, the cold waters of the deep Atlantic are prevented from flowing in, and a comparatively uniform temperature prevails in the depths of the Mediterranean. This being the case, there is little or no circulation—the water becomes to some extent stagnant, affecting in a marked manner the development of life in it.
Dr. Carpenter was astonished to find in the Mediterranean very few evidences of life at depths greater than eighteen hundred feet. "The dredge," he says, "brought up barren mud," and, however abundant life may be around its margins, its deeper portions are azoic. In the cold but freely-circulating waters of the Atlantic, animals are found at nearly the greatest depths—while the dredge is often filled from soundings of one to two miles. Whence the difference? "I found," says Dr. Carpenter, "the deep waters of the Mediterranean turbid, filled with fine particles of sediment which at last make the ooze of the bottom." The presence of this floating dust, even near the surface, is proved by the blueness of the water. Turbidity is known to be unfavorable to the development of many kinds of marine life. Prof. Dana has shown that a small quantity of sediment thrown upon a portion of a reef kills the polyps on that part, and the growth and distribution of coral-reefs are largely determined by this cause. But, another reason for the absence of life at the bottom of the Mediterranean is, the deficiency of oxygen in its waters in those depths.
Deep waters from the Atlantic and Mediterranean have been boiled off, and in the gases from the first there was twenty per cent, of oxygen, from the latter only five percent. But of carbonic acid there was from the first only thirty to forty per cent., while the latter furnished sixty per cent. Here, then, in the abundance of carbonic acid, and deficiency of oxygen, is a possible cause for the paucity of life.
But whence arises the deficiency of oxygen. Chiefly, perhaps, from the slow decomposition of organic matters, carried in by rivers and other agencies, and which may add to the turbidity referred to.
This state of things in the Mediterranean, and possibly in other inland seas, evidently arises from absence of circulation of the waters. Winds disturb the surface only, and Dr. Carpenter says there is in the Mediterranean no thermal circulation—or circulation which arises from inequality of temperature. It has been said that inequality of density caused by evaporation must produce some vertical circulation of the water, but density from lowering of temperature at the surface never exceeds the density of the deeper waters, and no circulation disturbs or mixes the superimposed masses.
The oxygen from the surface can only reach the deeper waters by diffusion, hence its deficiency at considerable depths. In the Atlantic, and doubtless in all open oceans, the waters are diffused, and mixed by a wonderful system of circulation, the dynamic agencies of which are not present, or only in a modified form, in the inland basins.
The well-known and often-criticised statement of Edward Forbes, that life ceases at a depth of three hundred fathoms, is confirmed by the researches of Dr. Carpenter, in so far as it relates to inland seas, the researches of Prof. Forbes being in the Ægean. The error consisted in applying the same rule to the open oceans, where a different one prevails, and this appears to have been the error of others rather than of Forbes.
Unequal Power of the Eyes.—Probably there are but few persons possessed of equal power of vision in both eyes. This circumstance, as is observed by a writer in Science Gossip, will doubtless account for some people being unable to appreciate the binocular microscope. The writer in Science Gossip has a friend who always found difficulty in studying with a binocular, in that he could never get the two glasses to blend. In 1851 he attended the Great Exhibition in London, and there his eyes were constantly ranging from short to long distances. After he had left the Crystal Palace he felt that his eyes were very much fatigued, and was at a loss to understand the meaning of it. By this and other circumstances he discovered that there was a focal difference in his eyes. One eye was far-sighted, while the other was near-sighted. For reading-purposes he wears a pair of spectacles in which the one glass is made for the far sight, while the other is a plain glass, the left eye being near-sighted, and consequently requiring no aid from spectacles with which to read. Instances are cited of persons who, while employing both eyes for ordinary vision, usually employ only one in reading. If any difference of the kind exists between the visual powers of a pair of eyes, it may be readily detected. Hold up a piece of card before one eye, so as to cut off its field of view, and then look at some object before you with the other. Then gradually bring the card before the other eye, and view the same object. If the object is seen with the same distinctness in each case, then your eyes are perfect as regards the balance of their foci: if not, then there is focal difference more or less decided. It would no doubt be advisable to take account of this very frequent difference of focus, in selecting a pair of spectacles.
Natural Grafting.—A writer in the Gardener's Monthly for August gives some instances of anastomosis, or natural grafting of plants, which came under his own observation. In The Popular Science Monthly for March, 1873, we gave Goeppert's theory, accounting for the continued life and growth, in some cases, of the stumps of pine and fir trees. Goeppert's explanation of the phenomenon is, that the roots of these stumps are nourished with sap derived from the roots of trees in their neighborhood, with which they are in contact. Such roots are found deeply embedded in one another, and so consolidated as to become practically continuous. The writer in the Gardener's Monthly, after briefly stating these facts, describes similar phenomena which he observed last spring among the branches of two apple-trees.
In one of these the limbs so crowded one another that it was resolved to cut one away. It was accordingly sawed off; but still it did not fall. It was then found that the dismembered branch was firmly united to a limb situated beneath it. With a hatchet the writer then cut it near the point of union; but the end of the branch still lives and thrives, bearing blossoms and fruit in season. Another tree was found, but a few yards distant from the first, which exhibited the same phenomenon of natural grafting. "I had never before," continues the writer, "seen or heard of such a case in an apple-tree, but I do not think it so difficult to account for as the condition of the coniferous trees. It is natural to suppose that the motion of the wind may occasion abrasion of the bark on the limbs of apple-trees, and thus prepare them for this natural grafting; but, in the case of roots underground, such cause for union cannot operate. In both these instances, it is worthy of remark that the trees were of the kind called American Pippin, or Grindstone." But surely there is no difficulty in conceiving of two roots from different trees growing into contact, when compressed together into a narrow space owing to the refractory nature of the soil. Under such circumstances they might rub away each other's bark at the point of contact, and establish between themselves such an exchange of living force as would constitute a life in common.
The Quinine-Supply.—The cultivation of the cinchona-tree in India, which was commenced in 1860, is making satisfactory progress. Near Darjeeling are two large plantations, one owned by the government, and the other by an association. The three principal varieties of the cinchona, officinalis, calisaya, and succirubra, were all planted at Darjeeling, with a view to find which variety would thrive best there. The officinalis, or gray-bark variety, failed utterly; the calisaya, or yellow-bark, has fairly succeeded; but the succirubra, or red-bark, has prospered beyond all expectation. There are now 2,500 acres under succirubra. A moderate estimate gives the produce of these plantations for the next three years at 200,000 lbs., calculated to produce 6,000 lbs. of quinine, and an equal amount of other valuable alkaloids.
Some years since a quinine famine appeared to be inevitable, as the cinchona-trees were fast disappearing in South America. "The drug," writes Berthold Seemann, "is almost as indispensable to mankind as air itself, and, aided by this silent agent, Europeans have been able to establish happy homes, busy factories, and flourishing colonies, in districts which, without this invaluable aid, would have simply become their graveyards. Our only wonder is, how we could ever have done without it, and what would become of us if the supply should ever fail. And the supply does begin to fail (1863), fail rapidly. It is known that 1,200,000 lbs. of Peruvian (or cinchona) bark are annually imported into England; and it is estimated that no less than 3,000,000 lbs., and probably a much greater quantity, are consumed every year throughout the world. The demand is daily increasing, and the drain upon the forests of New Granada, Ecuador, Peru, and Bolivia, has now been going on for two centuries.
"Thus, what with the excessive and unceasing demand for bark, and the reckless manner of collecting it, large tracts of country, formerly famous for their abundant yield, are now entirely denuded of almost every trace of cinchona-vegetation."
The Caterpillar Nuisance in Philadelphia.—For several years the measuring-worm preyed on the leaves of the trees in Philadelphia to such an extent that, early in the summer, scarcely any foliage would be left remaining. The English sparrow was introduced to counteract the destroyer, and performed its work so effectually that after a year or two no more measuring-worms were to be seen. But now, according to the Medical Times, another enemy of the trees has made its appearance, the caterpillar of the Orgygia leucostigma moth. As long as the measuring-worm was left unmolested, the caterpillar, which comes late in the season, found the struggle for existence a sharp one, its natural provision having been previously consumed by the worm. Now, however, it finds abundance of food, and is consequently prospering and rapidly multiplying. The sparrows will not attack it, protected as it is by its hairy coat. Perhaps some other feathered exterminator can be found to destroy the tribe; but, inasmuch as the sparrow is a very stubborn and pugnacious little fellow, it is a question whether he will allow any other bird to trespass on his domain. Meanwhile, the caterpillar pest is assuming formidable proportions, as witness the following passage from our medical contemporary: "At present, very many trees in this city have again put on the familiar, woe-begone look of old, hiding their misery with the merest tatters and shreds of leaves, 'But the new-comer doesn't drop on you!' Doesn't he though? If he does not drop he crawls, or gets on some way or other; and the man who has felt his long hairs tickling his neck, struck for a fly, and found in his hand a bare and bursted carcass, on his shirt-collar a stain, and down his back a bunch of tickling hairs, will vote the 'survival of the fittest,' in its latest form, an unmitigated nuisance."
Eating Alcohol.—It has been generally supposed that the alcohol formed in the primary fermentation of bread was all expelled by the process of baking. Mr. Thomas Bolas, of London, has communicated to the Chemical News the result of some experiments on this point. He shows that when about two ounces of ordinary bread is mixed with water and distilled, and the distillate is afterward purified, a perceptible quantity of alcohol may be obtained. He made quantitative analyses of six samples of fresh bread, obtained in so many shops in London, which gave of alcohol an average of 0.314 per cent. So that, when a man has eaten 100 pounds of fresh bread, he has consumed with it a little more than five ounces of pure alcohol.
The Grape-vine Blight.—M. Planchon, of the French Academy, an eminent botanist and entomologist, visited this country last summer to study the habits of the phylloxera, an insect which is ravaging the vineyards of France. Prof. Planchon was the first to discover that the blight of the grape-vine is the work of the Phylloxera vastatrix; and then Prof. Riley, State entomologist of Missouri, proved the American origin of the redoubtable ravager.
M. Planchon's investigations in this country fully corroborate Prof. Riley's observations as to the identity of the European and American insect, and as to the comparative immunity of certain American grape-vines. The Missouri entomologist's discovery of a species of acarus, which is the deadly enemy of the phylloxera, has attracted much attention abroad, and M. Planchon takes a supply of acari back with him to France, hoping by their aid to check the career of the destroying insect.
For five years, every remedy that imagination could suggest, under the stimulus of a reward of 20,000 francs, has been tried in France, but hitherto without success. The latest remedy, one from which great results were expected, is sulphuret of carbon. It was held that this substance is fatal to the phylloxera, but perfectly harmless to the vines. As to the first point, there appears to be no reason to question the beneficial effects of the sulphuret, but not so with regard to the second, if we may put any faith in the experiments of Lecoq de Boisbaudrant. According to him, sulphuret of carbon kills the vine as well as its parasite.
Migrations of Insects.—The following historical facts will give an idea of the enormous magnitude sometimes attained by migrating swarms of insects. After the defeat of Poltava, while retreating through Bessarabia, Charles XII.'s army was marching through a defile, when suddenly the men and horses were brought to a halt, being blinded by a living hail precipitated from a thick cloud which intercepted the light of the sun. The coming of the locusts was heralded by a whizzing sound like that which precedes a storm of wind, and the noise of their wings and of their bodies as they clashed together was greater than the roar of breakers on the sea-shore! General Levaillant saw, at Philippeville, Algeria, a cloud of locusts twenty to twenty-five miles in length, which, when it descended to the earth, formed a layer over an inch in thickness.
Toward the close of 1864 the cotton plantations of Senegal were destroyed, and a living cloud was seen to pass over the country from morning till night: the rate at which it moved showed that it was about fifty miles long; and this was only the vanguard, for when the sun went down a still denser cloud was moving on. The English traveller, Barrow, states that in Southern Africa, in the year 1797, these insects covered the ground to the extent of two square miles, and that having been driven by the wind toward the sea, they formed a drift near the coast nearly four feet in depth and fifty miles long! After the wind changed, the stench of their putrefying carcasses was recognized at the distance of a hundred and fifty miles.
The famines produced by the voracity of these acridians are not the only evils they cause to men and animals; a pestilential epidemic is oftentimes the result of the foul emanations from their rotting bodies. The invasions of these insects are veritable national calamities. In 1835 China was ravaged by them, and the sun and moon were obscured. Wherever they alighted the finest and richest crops were instantly devoured and the fields left bare; even the contents of the barns were to a great extent consumed by them. The people fled in alarm to the mountains. In the submerged districts, where there were no crops to devour, the locusts penetrated into the houses and destroyed the people's clothing. These ravages, which began in April, continued without interruption till the season of frost and snow.
Animal-like Functions of Plants.—In the Biological Section of the late meeting of the British Association, Dr. Burdon Sanderson read a paper on the electrical phenomena which accompany the contractions of the leaf of Venus's-Flytrap. It was remarked that in those structures in the higher animals which are endowed with the property of contracting when stimulated, viz., nerve and muscle, this property is associated with the existence of voltaic currents which have definite directions in the tissue. It became suspected that such was similarly true of the Sundew (Drosera), and Venus's-Flytrap (Dionæa muscipula) and some other plants. Mr. Darwin furnished the plants necessary for experiment to Dr. Sanderson in the laboratory of University College, London. The result is, that the anticipations of the existence of voltaic currents in these parts have been confirmed, particularly in the leaf of Dionæa. The doctor has established the fact that these currents are subject, in all respects in which they have been investigated, to the same laws as those of muscle and nerve. This may be regarded as one of the most interesting of recent biological discoveries.
Natural Varieties.—Nature's best efforts in the vegetable kingdom sometimes seem to be reached per saltum, and without any aid from man. Recently in England a first-class certificate was given by the Royal Horticultural Society for a fine variety of gooseberry, under the name "Kerson's Seedling Gooseberry." It turns out to be no garden seedling, but a wild one originally taken from a common hedge in the neighborhood of Peterborough. In like manner, the celebrated Bess Pool apple was originally discovered in a wood near Nottingham. It is noteworthy that the famous Lawton blackberry of this country was found wild at New Rochelle, in Westchester County, New York. It may be remarked of all these, and similar seedlings, that their specific excellence cannot be propagated by seeds but only by cuttings, stolons, or grafts.
Malformations.—Last winter one of our pupils at New Brunswick, N.J., communicated the fact that he had purchased, the previous autumn, of a huckster-woman in Newark, a pair of young ducks, each having four wings. The woman had twelve for sale, and said that the eggs were laid by a well-formed bird; that she hatched a brood of sixteen, every one of them having four wings. The youth said that his birds used both pairs of wings in flying, that is, in moving rapidly on the surface of the pond. They did not live long. Whether this was due to any defective vitality in the birds, or to any extraneous cause, could not be learned. But we turn from these traditionary facts to a catastrophe, which our own eyes have inspected, as having befallen a family of cats.
About a mile and a half from Freehold, N. J., live an intelligent family who have had for several years an annual litter of malformed cats. Several years ago a young male cat was brought from Allentown, some twenty miles distant. This cat had a deformity in one front-foot, which had six toes. It coupled with a cat of normal form and parts, and a litter of four or five was the result, all with six-toed front-feet. The she-cat became troublesome, getting into the pantry, and so was sent off. The kittens were disposed of, except one. With this the paternal cat united, and the result was four kittens, each having six toes on each fore-foot, and five on each hind-foot. This intermixing, as I understand, by this Grimalkin Turk, has gone on for some four years, and to-day, July 29th, I examined one of his daughters, some three months old, which has six toe on each of the hind feet, and seven toes on each of the fore-feet. The fore-feet are bifurcated; that is, they have, as it were, each two paws to one foot, the outer paw of each foot being much the larger, and having four toes; and the inner, or smaller paw, on each foot, having three toes. This kitten was one of a litter of four, all malformed precisely alike. On some points I could not get the exact information desired. But I should think that the vitality of these cats is becoming less and less, as they do not become common. To me it seems astounding when I attempt to conceive of the physical equation which enters into this erratic conception—the minuteness of the abnormal material which, plus the normal substance as imparted by the spermatozoön, gives the initial impulse to a result so eccentric. If, as Goethe declared, "it is in her monstrosities that Nature reveals to us her secrets," one would like to know something of the mode and motive of such a distribution of the life-force. During our inspection of Miss Tabbie it was all very well so long as we stroked her back with one hand. She purred, as expressive of true feline luxuriousness; and, what is not common, she even licked the other hand as indicating affection. But, when we meddled with her extremities, she evidently regarded it as taking personal liberties with unpleasant peculiarities; and instantly rewarded our duplicity by investing in our hand the seven talons concealed in that duplex napkin.—Samuel Lockwood, in American Naturalist.