Popular Science Monthly/Volume 41/July 1892/Popular Miscellany
The American Tea Plant.—The Ilex cassine, or youpon, is a shrub or small tree which grows in the Southern States, along the sea-coast, to not more than twenty or thirty miles inland, from Virginia to the Rio Grande. Its leaves and tender branches were once used by the Indians in the same way that the Chinese tea and the Paraguay tea are used. But the drinking of this tea has been nearly if not quite abandoned. A study of its history has been made by Dr. E. M. Hale, who has examined all the references to it he could find, and has started an inquiry into the reason why it has been abandoned, and the expediency of reviving its use. Its leaf, according to the analysis by Prof. Venable, of the University of North Carolina, contains caffeine. It is not so pleasant in odor and taste as the Chinese tea; but it seems to have some salutary properties which the latter does not possess, and may perhaps be more cheaply obtained. Dr. Hale estimates the extent of the land over which it grows as about forty thousand square miles, and suggests that careful experiments in cultivation and manipulation might result in furnishing our markets with a product that would be found in many cases an acceptable and useful substitute for the more expensive imported teas.
Many-toed Horses.—The derivation of the recent horse's foot with one digit from ancestors with polydactyl feet has been carefully traced by Prof. O. C. Marsh in his published papers on that subject. Several instances have come to the author's knowledge of existing horses presenting more than one toe. Julius Caæar's horse had this peculiarity. Its feet are described by Suetonius as having been almost human, with the hoofs cleft like toes. "It was born in Caæar's own stables, and, as the soothsayers declared that it showed that its owner would be lord of the world, he reared it with great care, and was the first to mount it. It would allow no other rider." The main functional toe of each foot of the horse is the third digit, corresponding to the middle finger of the human hand. In addition to these, two "splint-bones," one on each side of the main cannon bone, are present beneath the skin the remnants of two other toes possessed by ancestors of the horse. One or more of these splint-bones may become enlarged below and support phalanges, forming another digit beside the main one, or, more commonly, developing into a small external toe, with hoof. The occurrence of such extra digits in the recent horse is much more frequent than is generally supposed. Prof. Marsh has examined several living animals presenting this peculiarity, and has received photographs, drawings, and detailed descriptions of others. The extra digit may appear on one foot, when it is smaller than the main digit, and is usually on the inner side on the fore foot. It may often be entirely under the skin, with the only external evidence of it a prominence, in which its form may be made out. A corresponding extra toe may be present on the other fore foot; a second extra digit may exist with the others, but outside the main digit; with the extra inner toes of the fore feet, another of equal or smaller size may be present on one or both of the hind feet, almost always on the inside; in rare cases, both fore and hind feet may each have two extra digits fairly developed, and all of nearly equal size; or sometimes, besides the extra toes already described, which appear to be the second and fourth, the first digit, or pollex, may be represented by its metacarpal, supported by a distinct trapezium, all beneath the skin. A large majority of the polydactyl horses known to Prof. Marsh in this country have been raised in the Southwest, or from ancestry bred there, so that their connection with the mustangs or semi-wild stock of that region becomes more than probable. The fact that the tendency to reversion is much stronger where animals run wild must be taken into consideration in discussing the question of the origin of these animals.
Temperature of Lake Waters.—The investigations of Mr. A. T. Drummond on the temperatures of some Northern lakes and rivers have shown him that the Georgian Bay is, in its main expanse, a large body of cold water whose temperature, at its greater depths, is not much influenced by the heat of summer, while the central and southern basins of Lake Huron, although also receiving surplus waters from Lake Superior, stand in the line of inflow of the warmer waters from Lake Michigan and of their ultimate exit by way of the river St. Clair to the lower lakes, and are consequently somewhat warmer basins. Among the details of observations recorded in his papers, we find that tests at the rapids of the Richelieu River at Chambly seem to show that the motion of the water during the mile of continuous rapid raises the temperature of the water perceptibly. Rapid currents have, however, the effect of equal equalizing the temperature of the water. Under conditions appearing to be the same, and at points relatively near to each other, the water on the surface of the lakes and rivers is not uniform in temperature, but seems to flow in areas of different temperatures. It is impossible to lay down any general rule regarding the changes of temperature varying with the increase in depth. Apart from variations resulting at the different seasons, surface readings are affected by sunlight and cloud, gusts of wind, channel currents, the inflow of affluent streams, and the physical features of the surrounding land. Readings beneath the surface are affected by the depth of the water, by ordinary currents resulting from changes of level, by evaporation at the surface creating an upward flow of the water underneath, by the contour of the bottom, and by high winds which drive the surface waters before them, creating return currents underneath to take their place. The general rise of the temperature of Lake Ontario waters as the summer advances is at first slow, compared with the general rise of the temperature of the air, but, as midsummer is reached, the rise is more rapid both at the surface and at the bottom. The absorption and retention power of the sun's heat is most noticeable in the small streams and quiet pools. In the case of rivers, the air in direct contact with the warm surface of the water has its temperature in early August raised to from 1° to 5° above that of the air directly above, but in more exposed positions; and this increase in temperature, which is greatest at the point of contact, is, at one foot above the surface of the water, already to a considerable extent lost.
The Value of Human Testimony.—The argument of a book by Mr. Thomas Fitzarthur on the Value of Human Testimony is, according to the summary of The Spectator, that the value depends in a great measure on the importance attached by the witness to the facts to which he testifies. If the fact is insignificant, if his interest in it is languid, and it has no real bearing on his life, it is not to be supposed that he will take the trouble to attend to the matter with the care and the anxiety to be sure of what he sees or hears which is necessary to make his testimony of real weight for other people. But if it is a fact on which a great change in his own career depends, if it alters his whole life, his whole character, if it involves him in much labor and suffering, if it kindles in him an altogether new ideal of purpose, then we may be sure that his testimony is both honest and careful, and that, if it is supported by a great deal of other testimony of the same nature, it is in the highest degree trustworthy. Further, the author insists that its transmission through a long line of tradition does not invalidate its authority. We should not attach much value to details so transmitted. If we were dependent on testimony transmitted from generation to generation as to the numbers and character of the forces engaged in the battle of Hastings, we should not attach much weight to it. But such a long line of transmission would not diminish the value of the testimony as to the reality of that battle, and its result in the defeat of the Saxon and the victory of the Norman army. We should be well aware that that testimony must have been transmitted through a great many unwilling as well as a great many willing and triumphant witnesses. We should be well aware that all those witnesses must have had before their eyes the amplest evidence of the actual event, and of the revolution it brought about in the history of England. And we should never think of supposing anything so absurd as that at some specific date there was a deliberate conspiracy formed by hundreds of thousands of living Englishmen to alter the whole drift of the testimony they had received from their fathers, and invent a battle which never took place, or reverse its issue, and that that conspiracy should have succeeded in persuading the unborn generations to believe a gigantic lie. There could be neither machinery nor motive for such a successful conspiracy, and consequently the common sense of mankind at once rejects a hypothesis so audacious and absurd, with contempt.
Miss North's Animal Friends.—Miss Marianne North relates, in her Recollections, that while sketching an old Hindu temple at Blaune Watu, Java, she felt hungry and began eating a biscuit as she went on with her work. Shortly she was disturbed by a pull at her dress, and found a large monkey sitting beside her and looking reproachfully at her, "with the expression of 'How can you be so greedy? why don't you give me a bit?' Of course he did get it, and then departed and hid himself in the leaves overhead." At a place in California, where she stayed after all the other visitors had deserted it, "a stag," she says, "with great branching horns was my only companion; he had a bell round his neck, and used generally to live in front of the house, but liked human company; and when I appeared with my painting things he would get up and conduct me gravely to my point, and see me well settled at my work, then scamper off, coming back every now and then to sniff at my colors."
The Succession of American Floras.— No strongly defined line can be drawn, says Prof. Warren Upham, in a paper on the flora of the basin of the Red River of the North, "between different portions of the flora and fauna of the country from the Atlantic to the Rocky Mountains and from the Gulf of Mexico to the Arctic Sea. But great contrasts exist between the Eastern region, with its plentiful rainfall, and the dry Western plains, as also between the almost tropical Southern margin of the United States and the tundras beneath the Arctic Circle. In traveling from the once wholly forest-covered country of the Eastern States, across the prairies, to the far Western plains bearing cacti and sage-brush, there is observed a gradual change in the flora, until a very large proportion of the Eastern species is left behind, and their places are taken by others capable of enduring more arid conditions. Likewise, in going from St. Augustine or New Orleans to Chicago, St. Paul, Winnipeg, and Hudson Bay and Strait, the palmettoes, the evergreen live-oak, bald cypress, Southern pines, and the festooned Tillandsia, or Spanish moss, are left in passing from the Southern to the Northern States; and instead we find in the region of the Laurentian lakes the bur or mossy-cup oak, the canoe and yellow birches, the tamarack, or American larch, the black spruce, balsam fir, and the white, red, and Banksian pines; while farther north the white spruce, beginning as a small tree in northern New England and on Lake Superior, attains a majestic growth on the lower Mackenzie in a more northern latitude than a large part of the moss-covered barren grounds which reach thence eastward to the northern part of Hudson Bay and Labrador. Thus, although no grand topographic barrier, like a high mountain range, impassable to species of the lowlands, divides this great region, yet the transition from a humid to an arid climate in passing westward, and the exchange of tropical warmth for polar cold in the journey from South to North, are accompanied by gradual changes of the flora, by which in the aggregate its aspect is almost completely transformed."
Timber-testing.—The Forestry Division of the Department of Agriculture is engaged in making tests of timber, for the purposes of obtaining a better knowledge of the qualities of our commonest commercial timbers; of devising means of relating qualities to physical structure and appearance; and to establish, if possible, the influence which divers conditions of growth exercise upon the quality all conditions affecting the usefulness of the specimens in service. The records, which are preserved in duplicate, include the definition of the locality where the piece was cut, with its geological and climatological features; an exact description of the site and exposure, the soil, and the surrounding growth and undergrowth; the origin of the tree, its age and dimensions; the positions in the tree of the various test pieces submitted; and other points. It is expected to submit to the regular series of tests between one and two thousand test pieces of each species. It is hoped that when the work is done means will be afforded the engineer and architect to specify for timber of given quality, and also, by a rapid macroscopic and microscopic examination, to pass on each stick as to its coming up to the specification; and, further, of acquainting ourselves with the conditions of growth that produce given quality.
The Preservation of Historical and Interesting Scenery.—At the instance of the Appalachian Mountain Club, a law has been enacted in Massachusetts incorporating a Board of Trustees of Public Reservations, with authority to acquire, hold, arrange, maintain, and open to the public, under suitable regulations, beautiful and historical places and tracts of land within the Commonwealth. The property thus acquired, which can not, with its appurtenances, exceed two million dollars in aggregate value, is exempt from taxation, unless it is held longer than two years without being opened to the public. While the corporation enjoys these privileges, it is forbidden to own any capital stock or to make any division of property or income among its members, or any dividends. Mr. George F. Hoar has been chosen President of the Board. The trustees received last year several recommendations or offers of property as coming within the category of the purposes for which they are acting, and have considered the expediency of purchasing them; and Mr. J. B. Harrison, their agent, has made an inspection of the sea-coast towns of the State, with a view to the provision of public access to the beach and the establishment of seashore parks. The establishment of the board will enable the admirers of the scenery or history of any spot in the State to make that spot a reservation and to provide for its perpetual care, and will enable the proprietors of pleasure resorts and the people of communities which make money from the attractiveness of fine scenery to insure the perpetuation of such attractions and of their profits. Similar provisions should be made in all the States.
Characteristics of Star Spectra.—The general conclusion derived from the study of the spectra of the stars, says Prof. E. Pickering, in his account of the Henry Draper Memorial, is the marked similarity in constitution of different stars. A large part of them—the stars of the "first type"—have a spectrum which at first sight seems to be continuous, except that it is traversed by broad dark bands, due to hydrogen. Closer inspection shows that the K-line is also present as a fine dark line. If the dispersion is large and the definition good, many more dark lines are visible. These lines may be divided into two classes: First, those which predominate in many stars in the milky way, especially in the constellation of Orion; and, second, those present in the solar spectrum. Nearly all the brighter stars may be arranged in a sequence, beginning with those in Orion, in which the auxiliary lines are nearly as intense as those due to hydrogen. Other stars may be found in which these lines successively become fainter and fainter, till they have nearly disappeared. The more marked solar lines then appear, become stronger and stronger, and the hydrogen lines fainter, till they gradually merge into a spectrum apparently identical with that of the sun. Continuing the sequence, the spectra pass gradually into those of the third type. Certain bands become more marked, and the spectra of the third type may be divided into four classes, in the fourth of which the hydrogen lines are bright instead of dark. This spectrum appears to be characteristic of the variable stars of long period when near their maximum. It has led to the detection of several new variable stars, and has been confirmed in many of the known variables. Slight peculiarities are noticed in the spectra of many stars, but these deviations are not sufficient to affect the general law. Stars of the fourth type, whose spectra appear to be identical with the spectrum of carbon, are not included in this classification. Other stars, whose spectra consist mainly of bright lines, like those of the planetary nebula?, may be included with them in a fifth class.
The Reason of the Slave Trade.—A Moslem view of the slave trade is presented in the Saturday Review—not to excuse the traffic, but to show why it is carried on. The slaves are mostly children, "black, uncomely, and unpromising." They are not sought for the harem, in the conventional sense of that word. "The truth is, that certain conditions of domestic life among civilized Moslems exact a supply of slaves without regard to beauty or even to physical strength. The interruption of that supply has caused as much dismay and confusion as a law to forbid the employment of unmarried girls for household service might effect in England. It would be found at once that there were not matrons or widows enough to do the work, that few of them would undertake it, and fewer still were competent. Such a law would be evaded at every peril. No class of women in a Moslem community has the tradition of domestic service, as it may be called. Very commonly a free girl was taken into the household of some matron as a child, and there brought up; but she never dreamed of changing. One of the conditions was, and is, that her patroness shall provide a husband for her. Often enough, also, the child of such a protégée succeeds to her place when old enough, and thus very pleasing relations are established between families of different status. . . . The practice of adopting girl-children to train as servants becomes more and more common as slaves become scarcer. . . . A class of domestic servants is being formed which, in due time, will replace the slaves. But transformations of the sort are very, very slow in the East. Meanwhile the process is very disagreeable, even shocking, to Moslem housewives, and it is not at all surprising that they should pay heavily and run some risk to obtain a negro who is all their own."
Lake Beaches.—In his discussion of the beaches and their correlative moraines of Lake Erie, in the American Journal of Science, Mr. Frank Leverett shows that the belief of geologists now is that the phenomena do not demand a submergence of the land during the closing stages of the Glacial epoch; that, instead of a depression, there was a greater altitude than in the earlier part of the period; and that the result of investigation has been to reduce the noteworthy lakes connected with the closing stages of glaciation in Ohio to the one bounded by the beach lines that were recognized by the Ohio Geological Survey. The examination of the phenomena in detail leads to the conclusion that Lake Erie, in its earlier stages, was but a small body of water, its size being conditioned by the position of the retreating ice-sheet and by the height of the western rim of the basin it occupied.