Popular Science Monthly/Volume 12/January 1878/Popular Miscellany
Our Current Weights and Measures.—The absurdities of our present no-system of weights and measures surpass belief: they have their parallel in the absurdities of our present no-system of "orthography," but hardly anywhere else. The question of reducing to rule the current English orthography is now receiving attention, but the prospects of anything being done are gloomy enough. So, too, we hear occasionally of the necessity of reforming our weights and measures, but as yet no real progress has been made in any of the English-speaking countries. Our excellent contemporary, the Engineering and Mining Journal, in the course of an article favoring the adoption of the "metrical" system, gives the following apt illustration of the deplorable multiplicity of standard tons now in use:
"In a copper-works ore is measured and paid for by the (tribute) ton of 2,352 pounds, from the mine through the mill, till it comes out of the jigs, when suddenly it is transformed into a ton of 2,240 pounds (the difference, perhaps, going out in the tailings), which is the ton of the roasting and smelting furnaces and of the teamsters. This continues till the copper is sold or carried over some roads, when the ton shrinks again and becomes 2,000 pounds. At the iron-works there are still more tons, different from these, and on the railroads one will report the coal carried in tons of 2,240 pounds, and another connecting road uses the ton of 2,000 pounds. And in order to maintain the beautiful symmetry of our system, they, of course, rarely, if ever, state what kind of a ton is used in either case. Coal is mined and miners are paid by tons of various weights, from 3,000 pounds to 2,000 pounds. It is sold by tons of 2,240 and 2,000 pounds, and by tons running all the way down to 1,500 pounds. The use of the ton less than 2,000 pounds is called cheating, but the large purchasers, those who buy from a car-load (six tons) up, may get 2,240 pounds to the ton; but, if they buy from the same company's retail yard, they find the ton weighs no more than 2,000 pounds, if it does that. Coal is sold by bushels of 76 pounds and 80 pounds, by barrels, loads, hogsheads, and other 'standards,' the weights of which depend originally on the fancy of the individual, and subsequently on 'immemorial custom.' "
A Kansas Gas-Well.—About three years ago a company prospecting for coal discovered at Wyandotte, Kansas, a fountain of combustible gas. This gas, as we learn from the Western Review of Science and Industry, is now used by the company for steam-making, and by the owner of the farm where it is located for cooking and illuminating purposes. The gas, whether flowing or burning, is almost odorless, and its entire freedom from sulphur adapts it very well for use in the reduction of gold and silver ores. Notwithstanding a coal-vein of considerable thickness was discovered, the company has concluded to abandon coal mining for the present, and utilize this new gas-fuel. Nor is the latter adapted for heating purposes alone; it is also very valuable for light, inasmuch as it burns with a clear, bright flame, even without purification, and is free from the disagreeable odor accompanying coal-gas. The city of Wyandotte will soon be lighted by this gas, which, as it comes from the well, is of twelve-candle power. At small cost it can be purified so as to make it sixteen-candle power. The brine ejected from the well by the escaping gas is not strong enough for the manufacture of salt; it is recommended as a medicinal agent for the treatment of sundry diseases. The company contemplate erecting an extensive establishment for mineral baths.
A Plague of Rats.—Shortly after the settlement of the Bermudas by the British, the colony was infested with rats, which, in the space of two years, had increased so alarmingly that none of the islands were free from them, and even fish were taken with rats in their bellies. A writer in the Academy recalls some of the horrors of this plague of rats. The rats, we are told, had nests in almost every tree, and burrowed in most places in the ground like rabbits. They devoured everything that came in their way—fruits, plants, and even trees. Where corn was sown they would come by troops in the night and scratch it out of the ground; "nay," writes a contemporary chronicler, "they so devoured the fruits of the earth that the people were destitute of bread for a year or two." Every expedient was tried to destroy them. Dogs were trained to hunt them, who would kill a score or more in an hour. Cats, both wild and tame, were employed in large numbers for the same purpose; poisons and traps—every man having to set twelve traps—were brought into requisition; and even woods were set on fire, to help to exterminate them. Every letter written at this period by the plague-stricken colonists contains some account of the dreadful scourge. "Our great enemies the rats threaten the subversion of the plantation," writes one colonist in July, 1616. "Rats are a great judgment of God upon us," wrote another a year later. "At last it pleased God, but by what means is not well known, to take them away, insomuch that the wild cats and many dogs that lived on them were famished." There was universal joy at the sudden removal of such destructive vermin; and the all but despairing planters were enabled once more to resume their neglected occupations with spirit and energy.
Composition of Pumpkins.—Analyses of pumpkins, made by Prof. F. H. Storer, of the Bussy Institution, show that the rind of that vegetable is nearly three and a half times as rich in albuminoids as the flesh. The weight of albuminoids in the flesh is only about one-fifth as much as that of the carbohydrates, a proportion that has sometimes been found in turnips. Again, the inside or offal portion (including the seeds) of the pumpkin contains a large proportion of nitrogen, and the seeds yield a high percentage of oil. "The presence of such large amounts of oil, and of albuminous matters," adds Prof. Storer, in the Bulletin of the Bussy Institution, "would naturally go to show that pumpkin-seeds must be a highly-nutritious kind of food; and it may well be true that they are valuable for some kinds of animals, when administered carefully and in moderate quantity. But it has often been urged that the seeds are apt to do harm to animals that have eaten them. . . . There is little question that this idea is to a certain extent founded in fact." The dangers of using the seeds must, however, be both small and remote, since, as the author shows, New England farmers usually feed out the seeds with the flesh; still they should not be fed to milch-cows. Regarding the use of these seeds as articles of human food, the author quotes Pumpelly as saying that the kernels are eaten by the Chinese. In Egypt, too, pumpkin-seeds are eaten in the same way that nuts are eaten in other countries.
Ancient Man in Japan.—Prof. E. S. Morse has made an important discovery in the study of ancient man in this part of the world, lighting on evidence of the remains of prehistoric inhabitants of Nippon who apparently must have antedated even the Ainos. The eyes of this distinguished scholar, possessing as they do the rare quality of seeing, observed, while he was on his first trip to the capital from Yokohama, one of those significant shell-heaps which have been found in many countries and prove the high antiquity of the human race. This particular kjockkenmoedding is situated near Omori, on the line of the railroad, and is rich in evidence of a rude people that dwelt in Japan at a very early age. Prof. Morse has been engaged for many years in the study of these mounds, as found in Maine, North Carolina, and Florida. This heap, which is about ten feet in thickness at its greatest diameter, under a loam-deposit of six feet, and half a mile from the present shore of the bay, exhibits all the peculiarities of its type, containing bone, both in fragment and rudely fashioned into implements, and characteristic pottery. Some of the earthenware is curious enough, and is thoroughly representative of a development of the race coinciding with that of the ancient savages of America and Europe. The professor has made an exhaustive study of the deposit, and there seems little doubt of its true character. As, however, he has consented to address the Asiatic Society on the subject at its approaching meeting, we will not enlarge more particularly upon it at present, only advising all to avail themselves of the rare opportunity to hear one of the most fascinating of American lecturers on a theme of novel and great local interest.—Tokio Times.
Interesting Ethnological Specimens.—At a meeting of the Natural History Section of the Long Island Historical Society, Mr. Elias Lewis, of Brooklyn, exhibited several remarkable specimens of smoked Indian heads, brought by Mr. Ernest Morris from the hitherto little known region near the source of the Tapajos River, in Central South America. Some account of these heads was given by Mr. Lewis, and published in the Brooklyn Eagle. They are ten in number, and of great ethnological interest. The natives seemed to well understand the art of preserving them, but were exceedingly unwilling that Mr. Morris should get possession of the peculiar wood or root by the smoke of which they are preserved. A piece, however, was obtained and hidden by Mr. Morris in his luggage. The flesh and muscles of the smoked heads are shrunken somewhat, and quite hard, but the features are not distorted, and have a singularly lifelike appearance. All the lineaments of the face are clear and well defined. Most of the faces are tattooed. The hair is long, black, and very thick on the scalps, and the red paint with which the natives adorn themselves still remains in the hair of several of the specimens. The heads are ornamented with feathers, strings, and other appendages. In most cases the front teeth are wanting, having been knocked out previous to the smoking. Mr. Morris obtained the heads from the chief or principal man of one of the tribes in exchange for knives and other articles, and brought them away with great difficulty and some risk. In a letter from Mr. Morris it is stated that "the heads are those of the Parrebeate Indians, better known as the Parrintintins, who inhabit the land of the upper Tapajos. They are mostly taken in war and kept as trophies, and are preserved by smoke from a root which they call carrocopowpow. "They are very much as they appear in life, except that a cord is put in the mouth to carry them by, and the eyes are covered with a mass of wax. The practice was current among the Mundurucu tribe long since, but now appears to be practised only among the wild tribes which inhabit the country near the sources of the Tapajos and Hingu Rivers. The heads were taken about two years ago." One of the heads is that of a woman. Mr. Morris is now on his way to the Amazon for further exploration, and a part of the collection is offered for sale in his interest; the rest will be placed in the museum of the Long Island Historical Society.
A New Japanese Fruit-Tree.—We have received from Prof. R. H. Wildberger, of the Kentucky Military Institute, some of the fruit of the Guikgo biloba. This fruit was matured on a tree growing in the institute grounds, and is supposed to be the first ever produced in the United States. In a communication to the editor, Prof. Wildberger says that the tree is a native of Japan, and has been largely introduced into the United States and Europe, on account of its ornamental appearance. The one in the Military Institute flowered and fruited in June; in September the fruit began to turn yellow, and, after one or two frosts in October, to fall. This tree, which is about thirty feet in height, stands about eighteen feet from another of the same species which bore no fruit. Being absent at the period of flowering, our correspondent was unable to determine whether the species is diæcous, i. e., bearing pistillate flowers on one tree and staminate on another. Of the fruit he writes that it is a drupe or stone-fruit, about the size of a common wild-plum, much resembling it while green; but when mature it has a shriveled appearance, and is yellow in color. The sarcocarp, or fleshy part, is easily separable, disclosing the putamen, or stone, which is smooth and thin-walled, containing a kernel as large as a plum-stone, which has a pleasant taste. The sarcocarp has an acid, astringent taste, and a rather fetid odor. The kernel is said to be highly prized in Japan, and to be served at all banquets, being supposed to promote digestion and prevent flatulence.
New Order of Extinct Reptilia.—The museum of Yale College lately received the greater portion of a huge reptilian skeleton, found on the eastern flank of the Rocky Mountains, in beds that have been regarded by Prof. Marsh as corresponding nearly to the Wealden of Europe, and which may be classed as Upper Jurassic. Prof. Marsh writes that the remains are well preserved, but imbedded in so hard a matrix that considerable time and labor will be required to prepare them for a full description. The characters already determined point to affinities with the Dinosaurs, Plesiosaurs, and more remotely with the Chelonians, and indicate a new order which may be termed Stegosauria. The animal was probably thirty feet long, and aquatic; the body was protected by large bony dermal plates, which appear to have been in part supported by the elongated neural spines of the vertebræ. One of these dermal plates was over three feet in length.
Origin of the Moral Sense.—According to Darwin's theory the moral sense, conscience, is a development of the animal instinct of self-preservation. The scope of this instinct was at first confined within the individual; it was next extended to the group of animals in which it lived. In a low stage of human development, man would be bound by the ties of moral obligation at the most to those of his own tribe; but as he advances in civilization, and small tribes are united into larger communities, "the simplest reason," says Darwin, "would tell each individual that he ought to extend his social instincts and sympathies to all the members of the same nation. This point once reached, there is only an artificial barrier to prevent his sympathies extending to the men of all nations and races." Moral sense, in this theory, is an enlargement of an animal instinct, illumined by the light of reason. To many persons this way of accounting for the origin of morality is an abomination; it is supposed that thereby something is taken from the preëminent dignity of man. The objection is well met by Mr. J. A. Allen, who writes as follows in the Canadian Monthly: "I should be satisfied to resign my free-will to do wrong for a nature so constituted that I must always love and do the right. What, by instinct? Yes, by instinct, or by anything else. I should like to be always instinctively inclined to good, as the bee to make honey. But if I am denied this—if our nature is not yet adjusted to the requirements of the golden age—it is something to possess an unchangeable instinct of right at the very core of our being, which can neither be plucked out nor enslaved by the will, nor silenced by terror or bribes or flattery. But instinct! How undignified to be forced to do right by compulsion! What? By the compulsion of our own nature, by the imperious and imperial sense of our obligations to our fellow-men? On the contrary, I think that we should be ennobled by the possession of such a moral force." Of the mode in which the principles of morality are propagated Mr. Allen writes: "The maxims of morality, more or less true, come down to us by tradition, and root themselves in our youthful minds; but the solidified moral sense is transmitted by heredity, and forms an integral part of our very selves. It is, so to speak, our experiences, not from but in our grandfathers; the result stereotyped in our constitutions of all the ictuses of the various forces in this direction which had affected the whole line of our ancestry from the very first—transmitted feelings in transmitted structures."
The Waste of Wire-Works.—We are indebted to the Polytechnic Review for an account of a process in use at Worcester, Massachusetts, for utilizing the waste of a great wire-working establishment. Formerly the dilute sulphuric acid used for cleaning the wire was allowed to run into the sewer when it had become so charged with iron scale as to cease to "bite," and large quantities of refuse wire were employed only to fill up hollows in grading, or thrown into a heap. All of this waste material is, however, now converted into articles of commercial value by simple and comparatively inexpensive processes. The diluted acid, charged with iron, is heated in lead-lined tanks by means of steam passing through coils of copper pipe, the waste wire being thrown in. In about five days the acid, under the influence of heat, has taken up a large proportion of iron and become liquid sulphate of iron, which is then evaporated until it deposits the crystals known in commerce as copperas. Three tons of this solid sulphate are made per day from about twelve tons of the waste acid. The remaining liquid is returned to the receiving-tank, to be mixed with more of the waste acid and refuse wire; and so the work goes on in a continuous round. Even the waste of this product from waste is utilized. The settlings of the boiling-tank—oxide of iron—together with the waste copperas, an alkali, and an inexpensive substance to give "body," are roasted, ground, and transformed into a pigment equal to imported Venetian red. Of this the company makes about 500 barrels per month.
Spongy Iron Filters.—Dr. Gustav Bischof, inventor of the method of purifying water by filtration through spongy iron, recently detailed to the London Royal Society the results of sundry experiments on this and other filtering media. In the experiments fresh meat was placed on the perforated bottom of a stone-ware vessel, which was then filled to about two-thirds with the materials to be experimented upon, and lastly with water, care being taken to prevent the access of bacteria to the meat from any source save the filtered water. In Experiment I., spongy iron was used as the filter: after a fortnight's steady percolation of the water, the meat was fresh. Experiment II. was with animal charcoal: after a fortnight the meat gave signs of incipient putrefaction. Experiment III. was with spongy iron again, the water being allowed to flow for four weeks: the meat was perfectly fresh. In Experiment IV., which reproduced Experiment II., with the exception that the length of time was doubled, the meat was found to be soft and putrid. In the foregoing two experiments with spongy iron, the fine dust of that material had not been separated: in Experiment V. this was done: after four weeks the meat, again, was fresh. To prove that iron in solution was not in these cases the preserving agent, in Experiment VI. a stone-ware vessel was charged underneath the spongy, iron with pyrolusite and sand, so as to abstract the iron from the water before it came in contact with the meat: again the meat was fresh after four weeks' filtration. Experiment VII.: by a separate experiment it had been ascertained by Dr. Bischof that the oxygen is completely abstracted from water during its passage through spongy iron. To determine whether the absence of oxygen is the cause of the preservation of the meat, and whether the bacteria or their germs are killed or can be revived when supplied with oxygen, an evaporating basin was inverted over the meat. Though this must have retained a quantity of air in its cavity, the meat still was found fresh after four weeks. In the final experiment, fresh meat was placed at the bottom of a glass vessel and left standing covered, with about four inches of spongy iron and water. After three weeks the meat was very bad, thus showing that the action of the bacteria of putrefaction adhering to the meat was not prevented by the spongy iron above; and if, during the previous experiments with spongy iron, agencies capable of causing putrefaction had at any time come in contact with the meat—in other words, if the bacteria had not been killed in their passage through the spongy iron—the meat must have shown marks of their action.
The author accounts as follows for the action of this material: "I believe that the action of spongy iron on organic matter largely consists in a reduction of ferric hydrate by organic impurities in water. . . . Ferric hydrate is always found in the upper part of a layer of spongy iron, when water is passed through that material. The ferrous hydrate resulting from the reduction by organic matter may be reoxidized by oxygen dissolved in the water, and thus the two reactions repeat themselves. This would explain why the action of the spongy iron continues so long."
Marine Fishes in Lake Nicaragua.—The fish fauna of Lake Nicaragua has long been known to include a few species elsewhere found only in salt-water, as a Megalops, a shark, and a sawfish. How did these marine forms first enter the lake? Dr. Theodore Gill and Dr. J. F. Bransford, in a "synopsis" of the fishes of this lake, communicated to the Academy of Natural Sciences of Philadelphia, remark that this combination of species may have resulted—1. From the intrusion of the salt-water types into the fresh waters; or, 2. From the detention and survival of the salt-water fishes in inlets of the sea that have become isolated, and so, in course of time, fresh-water lakes. The latter hypothesis is declared the more probable one. By the uplift of the land an inlet of the Pacific might have been shut off from communication with the ocean, and the character of the water would be soon changed by the copious showers of that tropical country. The shark, sawfish, Megalops, and other species, mostly found in the sea, would have time to accommodate themselves to the altered conditions. At the same time, it must be remembered that most of the marine types in question are wont to ascend high up streams, and even into fresh water. Still, the numerous rapids of the river discharging from the lake discourage the idea that the species enumerated have voluntarily ascended the river and entered the lake. Of these fresh-water sharks of Lake Nicaragua, Squier says that "they are called tigrones from their rapacity," and that "instances are known of their having attacked and killed bathers within a stone's-throw of the beach at Granada."
Individual Hygiene.—Among the subjects discussed at a recent Educational Conference held in London was the importance of a knowledge of the laws of health. Mr. Thomas Bond, assistant surgeon to Westminster Hospital, asserted that, on an average, one-half of the number of out-patients treated by a hospital-surgeon suffer from diseases due primarily to a want of knowledge of the laws of health and cleanliness, chiefly in regard to dress, ablution, and ventilation. Varicose ulcers are most frequently caused by the use of elastic garters: these should never be worn by children, as the stocking can be perfectly well kept up by attachment of elastic straps to the waistband. If elastic garters are worn at all, they should be applied above the knee, and not below, where they obstruct all the superficial veins. Tight lacing, too, predisposes to varicose veins, in consequence of the abdominal viscera being pushed downward into the pelvis, causing undue pressure on the veins of the lower extremities. The hygienic use of clothes, the author said, is not so much to keep cold out as to keep heat in. In robust persons it is not at all necessary to put on extra clothing when preparing for out-door exercise: sufficient heat to prevent all risk of chill is generated in the body by exercise. But care should be taken to retain sufficient clothing after exercise, and, when at rest, to prevent the heat passing out of the body. The wearing of false hair prevents evaporation of the perspiration from the scalp, and so predisposes to baldness and other scalp-diseases.
Mr. Bond calls Urquhart, who introduced into England the Turkish bath, one of the benefactors of the age: this bath is, he says, stimulating and strengthening—a preventive as well as a curative in disease. Nor is this all: it promotes purity of mind and morals. He then suggests certain necessary precautions to be observed in the use of the Turkish and other baths. Coming to the subject of ventilation, he remarks on the feeling of lassitude felt by many persons in getting up in the morning. This is very often due to defective ventilation of the bedroom, or to the use of an undue amount of bedclothes. It is an error to suppose that a room can be ventilated by simply opening a window a little at the top: there must be an outlet as well as an inlet for the air. The best outlet is an ordinary fireplace, especially if there is a fire burning. Mr. Bond recommends for ventilation purposes the use of vertical pipes, communicating at the level of the floor with the outer air, and rising vertically to the height of four or five feet.
Marbleized Iron Utensils.—Sundry cooking-utensils of so-called "marbleized iron" have been subjected to chemical tests by Mr. William H. Dougherty, with the results given below, as stated in the "Proceedings" of the Academy of Natural Sciences of Philadelphia. The author, having heard reports that the enamel contained lead and arsenic, poured into a new dish of this ware a pint of good ordinary "white-wine" vinegar. This was then slowly evaporated nearly to dryness; then distilled water was added, and the whole treated with hydrosulphuric acid. The resulting precipitate of sulphide of lead was now dissolved in nitric acid and reprecipitated with sulphuric acid in presence of alcohol as sulphate of lead, and weighed over 24 grains. This result was further confirmed by reducing the sulphate to metallic lead with the blowpipe. From this it appears that the vinegar had dissolved out of the enamel enough lead to make about three grains of acetate of lead. Similar results were obtained from another experiment, in which citric acid took the place of the vinegar. A can of tomatoes in an acid condition was, digested in another dish of this ware and filtered, the filtrate being treated as in the foregoing experiments. In this instance slight but positive evidence was found of the presence of lead. The author could detect no arsenic. He states the composition of the enamel to be as follows: oxide of lead, 12 per cent.; silica, 47; alumina, iron, lime, potash, and soda, 41 per cent.
Was Man preglacial?—The Anthropological Institute of London lately held a conference on "the present state of the question of the antiquity of man," in the course of which the evidences of man's antiquity in England were very fully considered. The papers read at the conference by Prof. Boyd Dawkins, Prof. McKendrick Hughes, and Mr. R. H. Tiddeman, as also the highly-interesting discussion which followed, are reported in Nature. Our contemporary devotes several pages to the proceedings of the conference, but we have only space to indicate one or two of the more important lines of argument. First, as regards the validity of the arguments of Croll, Geikie, and others, that because in river-deposits and caves the bones of animals which now live only in hot climates are associated with the bones and other memorials of man, and as after the glacial period there is no evidence of such hot climate in England, therefore all these remains are preglacial or interglacial. To this it was objected that these animals of hot climates had preyed on such boreal animals as the reindeer; that the hippopotamus and rhinoceros in the Regent Park Zoölogical Garden do not suffer even in very cold weather; and that in the isle of Saghalien, to the north of Japan, the reindeer is preyed upon by the tiger, which crosses the ice in pursuit of its victim. Hence it follows that mammals are not good indicators of temperature. Mr. Tiddeman rested his argument for man's antiquity in Britain on the occurrence of a (supposed) human fibula and two hacked bones of goats in deposits older than the post-glacial. But Prof. Busk objected that the "fibula" was probably ursine, and, at all events, that it was altogether too insignificant a fragment on which to base any far-reaching conclusion. The goat-bones, hacked as if by the hand of man, were found in Victoria Cave, at the depth of fifteen and twenty-five feet respectively. But it was urged that these bones really belonged to a superficial stratum, and had fallen down to a lower level while the work of excavation was going on. But, even supposing them to belong to the levels from which they were taken, these bones are not decisive as to the age of the deposit in which they were found—a matter which is still in dispute. Arguments pro and contra were advanced by sundry members of the Institute, and the various evidences of the antiquity of man were considered in the light of geology, anatomy, the science of language, and paleontology. But no positive result was reached one way or the other; nevertheless, the conference was not without fruit, inasmuch as it has done much to remove misapprehensions, and to indicate the proper lines of research.
Electricity in War.—Mr. H. Baden Pritchard, in one of his communications to Nature on scientific principles involved in the art of war, gives a sketch of the employment of electricity in military operations. He says that the employment of electricity for exploding charges of powder was suggested by Franklin and Priestley; only very recently, however, have we been in a position to make proper use of this valuable agent as a means of firing charges at a distance. One of the first applications made of the subtile fluid was in the removal of the wreck of the Royal George at Spithead, nearly fifty years ago, when the explosion of the charges was brought about by what is termed a wire fuse, a short piece of platinum thread stretched between two copper wires. The platinum bridge, having less conducting power than the copper wires, presents a considerable resistance to any current of electricity that passes, and so becomes heated sufficiently to ignite gunpowder. "But for many purposes," remarks Mr. Baden Pritchard, "the wire fuse is ill adapted to the military and naval services. A voltaic battery is necessary to evolve the low-tension electricity required to yield sufficient resistance and heat, and such a battery made up of metal plates, and involving the use of acids, is a cumbersome apparatus. In 1853 Colonel Verdu, of the Spanish army, with the aid of a Ruhmkorff coil, succeeded in firing half a dozen charges simultaneously. Wheatstone and Abel followed in Verdu's footsteps, and while the former directed his attention to the construction of a portable frictional apparatus, the latter busied himself in the preparation of a fuse inclosing a compound more easily explosible than gunpowder—a fuse which still holds an important place among warlike stores."
Alternation of Seasons and Tree-Growth.—The fact that the exogenous plants of the preglacial epoch show concentric growth-rings has been by many writers regarded as proof positive that in these times the earth's axis must have been inclined as at present, and that there must have been then, even as now, alternating seasons. But is alternation of seasons necessary to the formation of rings?
This question is considered by Dr. C. B. Warring, in a paper read before the New York Academy of Sciences, an extract from which has appeared in the American Journal of Science and Arts. The problem might be solved experimentally, says Dr. Warring, if we could secure for plants a uniform temperature throughout the year. The nearest approach to such a condition in this latitude is found in greenhouses. Exogenous plants so placed, e. g., the orange and lemon, form growth-rings as regularly as do forest-trees. The author has found it difficult to obtain any information as to the formation of these annual markings in exogenous plants growing in tropical regions. But the facts appear to show that, in the uniformly warm climate of the tropics, rings are formed as regularly as in our own latitudes. True, in the tropics there are semi-annual changes from wet to dry, and from dry to wet, dependent on the earth's axial inclination; but, as the author remarks, even when there is absolutely no variation, the rings are formed. For instance, man-groves, growing on the muddy margins of tropical rivers, having from year's end to year's end uniform temperature and moisture, present clearly-defined rings of growth. Then the Cycads require several years to form one ring. The author's conclusion is, that "these circles have their origin in cycles of activity and repose, implanted in the constitution of the plant, which would continue to manifest themselves although there were no climatic variations. It is true," he adds, "that where seasonal variations exist, the successive stages of activity and rest are for obvious reasons synchronous with them, but they are not absolutely dependent on them. . . . The existence, therefore, of these markings in the ancient flora gives no information as to the existence at that time of seasons, and, so far as they are concerned, we are left free to adopt any conclusion as to the inclination of the earth's axis which may appear to us most reasonable."
Preservation of Wood under Water.—The effects of long-continued submergence in water on oak-wood are remarkable, and several instances are cited in the "Annales des Ponts et Chaussées," by M. Charrié-Marsaines, of oak being transformed so as very closely to resemble ebony. Thus, some pieces of oak taken in 1830 from an old bridge at Rouen, which had stood about 700 years, were found to resemble ebony, the modification being clue to the presence of peroxide of iron. M. Charrié-Marsaines himself having occasion, in constructing a discharge-sluice on the Rhine, to demolish an old military dam constructed in 1681 by Vauban, and based on a platform of oak, found this wood to have a dark color quite like that of ebony, and very great hardness, as was found on trying to cut it for use in the new works. The wood had then been 146 years in a soil constantly soaked by water, owing to the permeability of the layer of gravel here forming the bed of the Rhine.