Popular Science Monthly/Volume 24/March 1884/Popular Miscellany

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Sub-aerial Decay of Rocks.—Professor T. S. Hunt publishes, in the "American Journal of Science," an elaborate paper on the "Decay of Rocks," in which he insists that recent geological studies afford evidence that a sub-aerial decay both of silicated crystalline and calcareous rocks has taken place universally and from the most ancient epochs, and that it was very extensive in pre-Cambrian times. He further insists that the materials resulting from this decay are preserved in situ, in some regions by overlying strata; in others by the position of the decayed material with reference to denuding agents; and that the process of decay, though continuous through later geological ages, has, under ordinary conditions, been insignificant in amount since the glacial period, on account of the relatively short time that has elapsed, and also, probably, on account of changed atmospheric conditions in the later time. The process of decay, he believes, "has furnished the materials for the clays, sands, and iron-oxides from the beginning of Palæozoic time to the present, and also for the corresponding rocks of Eozoic time, which have been formed from the older feldspathic rocks by the partial loss of protoxide bases. The bases thus separated from crystalline silicated rocks have been the source, directly and indirectly, of all limestones and carbonated rocks, and have, moreover, caused profound secular changes in the constitution of the ocean's waters. The decay of sulphureted ores in the Eozoic rocks has given rise to oxidized iron-ores, and also to deposits of rich copper-ores in various geological horizons." Finally, Professor Hunt maintains that "the rounded masses of crystalline rock left in the process of decay constitute not only the bowlders of the drift, but, judging from analogy, the similar masses in conglomerates of various ages, going back to Eozoic time; and that not only the forms of these detached masses, but the outlines of eroded regions of crystalline rocks, were determined by the preceding process of sub-aërial decay of these rocks."

"Colds."—The views of Dr. Page on the subject of "catching cold," published in the "Monthly" for January, having been sharply criticised as unsound and extreme, we give below an extract on the same subject from the London "Lancet," a scientific medical authority of the highest grade: "A person in good health, with fair play, easily resists cold. But when the health flags a little, and liberties are taken with the stomach or the nervous system, a chill is easily taken, and, according to the weak spot of the individual, assumes the form of a cold, or pneumonia, or, it may be, jaundice. Of all causes of 'cold,' probably fatigue is one of the most efficient. A jaded man coming home at night from a long day's work, a growing youth losing two hours' sleep over evening parties two or three times a week, or a young lady heavily 'doing the season', young children at this festive season over-fed and with a short allowance of sleep, are common instances of the victims of 'cold.' Luxury is favorable to chill-taking; very hot rooms, soft chairs, feather beds, create a sensitiveness that leads to catarrhs. It is not, after all, the 'cold' that is so much to be feared as the antecedent conditions that give the attack a chance of doing harm. Some of the worst 4 colds happen to those who do not leave their house or even their bed, and those who are most invulnerable are often those who are most exposed to changes of temperature, and who by good sleep, cold bathing, and regular habits, preserve the tone of their nervous system and circulation. Probably many chills are contracted at night or at the fag-end of the day, when tired people get the equilibrium of their circulation disturbed by either over-heated sitting-rooms or underheated bed-rooms and beds. This is especially the case with elderly people. In such cases the mischief is not always done instantaneously, or in a single night. It often takes place insidiously, extending over days or even weeks. It thus appears that 'taking cold' is not by any means a simple result of a lower temperature, but depends largely on personal conditions and habits, affecting especially the nervous and muscular energy of the body."

How and where Malaria thrives.—The health-officers of New Britain, Connecticut, have made an instructive report concerning the prevalence of malarial diseases in that town, and their connection with certain supposed causes. The causes of malarial and other miasmatic diseases are not identical, though they are similar, and the two classes not infrequently occur in a given locality at the same time; and the hygienic measures required to prevent them all are the same. The essential conditions for the development of malaria appear to be: the presence of the malarial germ; a high temperature and dry atmosphere; and favorable conditions of the soil; and the absence of either of them will suspend or prevent the action of the poison. We have power only over the third condition. "A generous rain in the vicinity has, we think, invariably suspended its action. And yet a previous condition of moisture is essential to its manifestation. All deposits of vegetable matter, such as muck, sink-drainage, heaps of decaying vegetable matter, or even wet, spongy land, furnish the essentials for its support; but it is requisite that the soil shall have been very wet, or covered with water some portions of the year." A generous crop of grass, and perhaps of other vegetable substance, has been known to prevent malaria. In 1880 nearly all the families in the neighborhood of some lots which were largely a deposit of muck had malaria. The lots were plowed, dragged, and sowed with grass-seed, and the appearance of the crop of grass and weeds was attended by a disappearance of chills and fever. Two or three other instances are mentioned in the same town, in which fever-and-ague was banished by giving a similar treatment to tracts of swampy and mucky soil. Another case is specified where malaria was prevented by the drying up of the sewerage and sink-water which usually found its outlet through a system of ditches cut in muck. Preparations were making to lay tiles in the ditches and fill them up, but, before this was done, a heavy rain washed them out, and "caused the prevailing sickness to abate as suddenly as it had commenced." From the first, malaria has not prevailed in those parts of the city where vegetable deposits and filth have been absent, and the health of the streets in which sewers have been laid has been remarkably good.

Can Dogs be taught to read?—Under the title "Instinct," Sir John Lubbock writes as follows in a recent number of the "Spectator":

"Sir: Mr. Darwin's 'Notes on Instinct,' recently published by my friend Mr. Romanes, have again called attention to the interesting subject of instinct in animals. Miss Martineau once remarked that, considering how long we have lived in close association with animals, it is astonishing how little we know about them, and especially about their mental condition. This applies with especial force to our domestic animals, and above all, of course, to dogs. I believe that it arises very much from the fact that hitherto we have tried to teach animals, rather than to learn from them— to convey our ideas to them, rather than to devise any language, or code of signals, by means of which they might communicate theirs to us. No doubt, the former process is interesting and instructive, but it does not carry us very far. Under these circumstances, it has occurred to me whether some such system as that followed by deaf-mutes, and especially by Dr. Howe with Laura Bridgman, might not prove very instructive, if adapted to the case of dogs. Accordingly I prepared some pieces of stout cardboard, and printed on each in legible letters a word, such as 'food,' 'bone,' 'out,' etc. I then began training a black poodle, 'Van' by name, kindly given me by my friend Mr. Nickalls. I commenced by giving the dog food in a saucer, over which I laid the card on which was the word 'food,' placing also by the side an empty saucer, covered by a plain card. 'Van' soon learned to distinguish between the two, and the next stage was to teach him to bring me the card; this he now does, and hands it to me quite prettily, and I then give him a bone, or a little food, or take him out, according to the card brought. lie still brings sometimes a plain card, in which case I point out his error, and he then takes it back and changes it. This, however, does not often happen. Yesterday morning, for instance, he brought me the card with 'food' on it nine times in succession, selecting it from among other plain cards, though I changed the relative position every time. No one who sees him can doubt that he understands the act of bringing the card with the word 'food' on it, as a request for something to eat, and that he distinguishes between it and a plain card. I also believe that he distinguishes, for instance, between the card with the word 'food' on it and the card with 'out' on it. This, then, seems to open up a method which may be carried much further, for it is obvious that the cards may be multiplied, and the dog thus enabled to communicate freely with us. I have as yet, I know, made only a very small beginning, and hope to carry the experiment much further, but my object in troubling you with this letter is twofold. In the first place, I trust that some of your readers may be able and willing to suggest extensions or improvements of the idea. Secondly, my spare time is small, and liable to many interruptions; and animals also, we know, differ greatly from one another. Now, many of your readers have favorite dogs, and I would express a hope that some of them may be disposed to study them in the manner indicated. The observations, even though negative, would be interesting; but I confess I hope that some positive results might follow, which would enable us to obtain a more correct insight into the minds of animals than we have yet acquired."

Salts in Rivers and in the Sea.—The sea, it is well understood, is fed with salt as well as with water, by the rivers. The question then arises naturally, How is it that the rivers—admitting that they are mildly salt, although they appear to be fresh—differ from the ocean in the kind as well as in the strength of their saltness? Mr. W. Mattieu Williams answers the question by showing that, when sea-water is evaporated, sulphate of lime is the first salt to be deposited, while chloride of sodium, sulphate of magnesia, chloride of potassium, and the bromides, are deposited later. Hence, when the sea-water reaches the point of saturation with sulphate of lime, no more can be dissolved in it, but all additional supplies must be deposited. Moreover, if a soluble salt of lime were brought into the sea, its lime would combine with the sulphuric acid there combined with magnesia, or soda, or potash, which would, in obedience to a curious chemical law, leave those bases to combine with that one which would form an insoluble compound. Thus the total quantity of lime in sea-water is limited by the solubility of sulphate of lime, and this amounts to only about one part in four hundred of water.

The Caribs and the Greeks.—Mr. A. J. Van Koolnijk has published in the "Journal of the Dutch Geographical Society" an account of Carib tombs and relics which have been found in the Island of Aruba, off Dutch Guiana. Among the relics are potteries of good workmanship, elaborately ornamented and painted in a variety of colors obtained on the island. Some of the more common ornaments are figures of frogs and frogs' heads, which indicate that the Indians had considerable respect for those animals. Many of the ornaments, the handles of the vessels, and the skill with which the reliefs were finished, reminded the discoverers of Greek patterns. Some of the vessels, too, bore figures which were thought to be inscriptions or hieroglyphics, and a remarkable resemblance was traced between these characters and the letters of the Greek alphabet. This leads our Dutch antiquary to consider the question whether there may not have been some kind of a connection between these Caribs and the ancient Greeks. Ch. Rümelin is quoted as having suggested the possibility of looking for the origin of the northern tribes of Colombia, through the Guanches of the Canary Islands, to the Foulahs of the Soodan. Cyries also speaks of having seen hieroglyphic figures representing the sun, moon, and various animals, roughly cut on the granite rocks of Guiana at such heights that ladders had to be used to reach them.

The Stone Age in Africa.—Herr Richard Andree has accumulated a large mass of evidences of the existence of a stone age in Africa a point which has hitherto been involved in much doubt. The Djurs, on the White Nile, still hammer their iron with a block of granite; smoothed stones are still used for hammer and anvil between the east coast and the Tanganyika Lake; the Hottentots and Bushmen dig roots with perforated stones; the Arabs in Egypt curry their shorn sheep with flint; the Bushmen tip their arrows with bone, and the Gabiri, in Bagirmi, with clay. Stories, which are reminiscences of the days of stone instruments, are told among the Hereros, and among the Bazimba of Madagascar. When the Europeans discovered the Canary Islands, they found the Guanches in the midst of a stone age. This much we know of the present use of stone. The historical evidences are scarce. Diodorus Siculus says the Libyans threw stones at their enemies, and Agatharcides says that the Ethiopians tied stone points to their arrows, while Strabo says they tipped them with antelope-horn. Vessels and implements of stone have become quite common among the "finds" of Egypt, and in all the countries and the deserts to the western border of Morocco. While not more is known about the stone evidences than about the other features of the intermediate countries, flints and stone vessels, of both crude palæolithic and more highly-finished forms are found at numerous places in the southern point of Africa, from the mouth of the Orange River to Delagoa Bay. The implements are very similar in form and material to the European finds, and present the same puzzle in the occurrence of nephrite among them. Assuming that evidences will be found at least as abundantly in the countries which have not yet been examined for them, the conclusion is drawn that the Africans, although they have been using iron as far back in historical times as our knowledge extends, had also a stone age.

Indistinctness of Race Divisions.—Professor Léon Rosny, in his forthcoming work on the "Danubian Principalities," says, speaking of the nationality of the Roumanians, that that people confirms a view which he has held for years, and which is also M. Renan's view, that the matter of nationality is very largely a question of feeling. Many different elements may have contributed to the formation of a Roumanian nationality, but the chief one has been the fancy that the people of Moldavia and Wallachia were descended from a mixture of the ancient Dacians with Trajan's soldiers, and were, therefore, the Romans of the East, whose mission it was to guard the interests of the Latin race in that part of Europe. Reminiscences of Roman antiquity are still current in the country, as, for example, in a popular dance, the Kalusar, which represents the rape of the Sabine women. Conversely, the Tartars of the Dobrudja are composed of a great variety of types, from that of the pure European to that of the most pronounced Mongolian, but they all pass alike for Tartars. These things suggest, again and again, the thought that the characteristic traits which are held to be most decisive in determining the differences between the groups of mankind are in reality very flexible and changeable. Physical tokens are of service only for the establishment of two or three grand divisions among men, and the value even of these divisions is becoming more and more subject to criticism. Linguistic distinctions, on which ethnographic classifications have for some time been assumed, are likewise very fallacious. People have been capable of changing their vocabulary and their grammar, and even of discarding their whole language and adopting another of different spirit. The groups of the human race are, as a whole, the product of historical changes in the different phases of their existence, and the influence of the surroundings in which they have developed themselves. Professor Halévy supports M. Rosny's theory, and believes that nations may change their language, their disposition, and their moral character, according to the surroundings among which they live, and according to their institutions. Africans, for example, show a change from the moment they become Mohammedans. The word "race" should no longer be used in ethnology. "When I was in Abyssinia," he says, "during the war between England and King Theodore, it was quite impossible to distinguish a Hindoo in the British service, when he was stripped, from a native Abyssinian. Even Theophrastus was aware of the striking similarity, and classed the Indians and Abyssinians together as Ethiopians."

The Check in the Growth of France.—The attention of French economists has been drawn for several years to the fact that the population of their country is not increasing, but shows rather a tendency, in many parts of the country, to diminish. The tendency is steadily manifested, in several departments, to a greater degree than in others, and has been maintained with considerable uniformity in those departments where it is most marked. The departments in which the decrease is most observable are the group in Languedoc and the group in Normandy. Of the five Norman departments, only one, that of the Lower Seine, shows an increase, and the increase there is solely due to the attraction of the large towns of Havre and Rouen. The tendency of population to gravitate toward the cities, at the expense of the rural districts, is as marked in France as in other countries, and contributes its quota toward retarding the growth of the country as a whole; for mankind are less prolific in towns than in the country. A few departments show an increase of population, and these, curiously, are about evenly divided between the richest and the poorest departments in the nation. The cause of the stationary condition of the population is found, by those who endeavor to account for it, in the evenly comfortable situation of the people. They are contented with things as they are, and avoid having large families, in order to evade extra exertion and prevent the diminution of their estates that would follow if there were many heirs to divide them among. Every one aims to live and save, so as to leave his children as well off as himself, and a little better off if possible. Hence very few have more than three children. All the large towns have increased enormously during the present century, at such a rate that, if the population of the whole country had increased at the same rate, France would have had seventy-five million inhabitants, or would have been as densely populated as England. Had it not been, in fact, for the augmentation of the populations of Paris, Lyons, and Marseilles, the population of all France would have actually diminished during the last five years. This augmentative population, except as it is of foreign origin, contributes, as we have seen, to the tendency to depletion of the aggregate.

Anthropology in Italy.—Anthropology is studied in Italy with considerable zeal, and nearly every large town has its collection and its specialist of repute. The country, as may be judged from the figure it has made in history, is rich in monuments dating from a very great antiquity. In upper Italy earth-walls have recently been discovered on the mountain-heights, which are attributed to the Celts. The plains of Lombardy and Emilia have furnished numerous remains of lake-dwellings, which have been studied by Pigorini, Strobel, and Chierici, and are represented in the collections of Parma and Reggio. Not less important are the Etruscan necropolis of Margabotto and that of the Cerlosa of Bologna. Bologna has its newly built Museo Civico under the direction of Gozzodini, and the accomplished geologist Capelini, who has discovered traces of cannibalism in a cave on the Island of Palmaria. The Olmo skull, which Cocchi regards as post-Pliocene, and which may be compared with the Cro-Magnon and Steeten skulls, is in the geological collection of this city. Mantegazza has founded an anthropological and ethnological museum in Florence, with Miloni in charge of the Etruscan and Schiaparelli of the archaeological departments. Perugia, too, has Etruscan antiquities, and Belluci is collecting prehistoric stone implements there. Pigorini has established a prehistorical and ethnological museum at Rome, where Michael St. de Rossi has won much honor by his researches. Nicolucci, who has founded an anthropological collection at the University of Naples, has examined about a hundred skulls, and has found them to be mesocephalic Grecian skulls, very like those still typical in the region.

Two East African Tribes.—Some interesting information respecting East African tribes has been obtained by the London Geographical Society from the notes of the Rev. T. Wakefield, missionary at Ribé, near Mombasa. Kavirondo appears to be the most important country on the eastern shore of the Victoria Nyanza, and is described as a great grass-clad plain, with a few detached hills and clumps of trees, but altogether without forests. The people are tall and powerfully built, of a deep black, and with thick lips and flat noses. They wear their hair short, or dress it elaborately, or shave it all off but a tuft on the crown, or shave half the head, or a few patches only, according to their taste. The women tattoo the stomach and the back, but the men do so only rarely. Dress is almost unknown. The women are content with a string worn round the waist, to which they attach a tail-like appendage made of bark. They wear no ornaments, but smear themselves with disagreeable (to whites) substances. The men wear iron bracelets on their fore-arms, and above their elbows. Their spears are long and have short blades, and their shields are made of buffalo-hides. Neither swords nor knives are in use. Both sexes work in the fields. Millet, beans, bananas, and large crops of sweet-potatoes are grown, and two harvests are gathered in the year. A thick porridge, on festive occasions, made with milk, constitutes the staple food, and is eaten with the hands. Cattle, sheep, and goats are raised. The huts are circular and roomy, and high enough for a man to stand upright within them. Another people, the Wa-Ukara, are likewise tall and muscular, and have a similar variety of tastes about their hair, They paint their bodies red, with clay mixed in oil, and their arms and legs with white; tattoo their stomachs and upper arms and have few ornaments. Women wear kilts of bark-cloth and skins, and men a longer garment of like material. They live in circular huts, built over pits three feet deep, and covered with conical roofs. They marry only when full-grown, and pay the dowry for their wives in cattle and goats. They grow a variety of crops, and pound their corn or millet in a wooden mortar, or grind it on a flat stone, beneath which a cowhide is spread out to receive the flour. Their domestic animals are cattle, goats, sheep of a superior kind, dogs, and fowls, but cats are not known. Their blacksmiths manufacture hoes, axes, and spears; and they produce cooking-pots of clay and baskets of wicker-work. Ukara contains a large number of populous villages.