Popular Science Monthly/Volume 9/June 1876/Miscellany
A Moth that bores for its Food.—The order of Lepidoptera, which includes moths and butterflies, is almost universally characterized as possessing a flexible trunk, by means of which the insects suck up the nectar of flowers. Indeed, the possession of a flexible trunk is commonly regarded as one of the distinguishing characteristics of this order. A few years ago, however, a French botanist, M. Thozet, then residing in Australia, discovered a moth (Ophideres fullonica) which possessed a trunk so rigid as to be able to pierce the rinds of oranges and suck their juice. Another Australian observer having since called attention to the depredations of this moth, M. J. Künckel was led to examine the trunks of Ophideres which had been sent to him from Australia by M. Thozet. This trunk he declares to be a perfect instrument, and says that it would be an excellent model for the making of new tools to be employed in boring holes in various materials. It resembles the barbed lance, the gimlet, and the rasp, and hence can pierce, bore, and tear, at the same time allowing liquids to pass without impediment by the internal canal. The two applied maxillæ constituting the organ terminate in a sharp triangular point, furnished with two barbs; then they become enlarged, and present on the lower surface three portions of the thread of a screw, while their sides and their upper surface are covered with short, strong spines, projecting from the centre of a depression with hard and abrupt margins. The purpose of these spines is to tear the cells of the orange pulp, as the rasp serves to open the cells of the beet-root, in order to extract sugar. The upper region of the trunk is covered below and on the sides with fine, close-set striæ, arranged in half-screws, which give it the properties of a file; the striæ are interrupted here and there by small spines of soft consistence, which serve for the perception of tactile sensations. The orifice of the canal is situated in the lower surface, below the first screw-third. All this will be seen better from the annexed figures:
Trunk of Ophideres fullonica.—A, in Profile; B, from below; C, from above; t, Interior Canal; o, Orifice of the Canal.
On investigation, M. Künckel has found that all the species of the genus Ophideres possess a similar terebrant trunk. This circumstance establishes a closer relationship between the Lepidoptera, the Hemiptera, and certain Diptera in which the maxillæ are adapted to pierce tissues.
As we learn from Prof. A. R. Grote, the group of Noctuidæ to which Ophideres belongs, called by Borkhausen Fasciatæ, is represented by only a few forms in Europe, but it is largely developed in the tropics of both hemispheres. The peculiar structure of the maxillae observed in Ophideres has not been found in any of the North American genera of the group. In the genus Catocala, which is largely represented in North America, the spiral tongue or trunk is simply furnished with lateral papillae, appearing like serratures, toward the extremity of the trunk.
Cunning of the Adder.—A correspondent of the Milwaukee Sentinel confirms Mr. Lewis's observations on the cunning of the adder (in the February number of the Monthly). This correspondent states that, over thirty years ago, in Leeds, Greene County, New York, his attention was one day attracted by the plaintive cry of a cat. Looking into a garden, an adder was seen near the cat. The cat seemed to be completely paralyzed by fear of the adder; she kept up the plaintive cry, as if in great distress, but did not take her eye off the serpent, or make any attempt to attack or escape. Soon the snake saw that human eyes were observing him, and he commenced to crawl slowly away. "I then," continues the writer of the narrative, "concluded to release the cat from its trouble. I took a garden-rake and put it on the snake's back, and held it without hurting it. As soon as I had the snake fast in this position, it raised its head, flattened it out, and blew, making a hissing noise, and something resembling breath or steam came from its mouth. When that was exhausted I removed the rake, and the adder turned over on its back, lying as if dead. With the rake I turned it over on its belly again, but it immediately turned on its back. This was repeated several times. At last it was taken out of the garden, laid in the road, and we all retired to watch its movements. It commenced to raise and turn its head slowly (looking about the while), until entirely on its belly, and started at full speed for a little pool of water in the road, from which it was raked out and dispatched."
Measuring Distances by Sound.—The Prussian correspondent of the London Times makes mention of an instrument devised by Major Le Boulanger, of the Belgian Artillery, which, with great accuracy, indicates the distance between two armies from the report of their guns. The moment the enemy fires a shot, the action of the report upon the "telemeter" marks the distance to a fraction. The instrument is entirely self-acting, easily kept in order, and requires no particular experience or intricate calculations to use it aright. The experiments to which it has been subjected in Prussia and in some other countries are stated to have been completely successful as regards cannon. Experiments in the rifle-grounds are still going on. Even should the invention be confined to artillery, its effect must be tremendous, considering the present deadly efficiency of firearms. One of its principal advantages, it is supposed, will be to enable gunners in a coast-battery to determine the position of a hostile ship—a calculation hitherto fraught with special difficulty.
Sir John Lubbock on the Habits of Ants.—Sir John Lubbock still continues his observations of ants, and at a recent meeting of the Linnean Society of London read a paper in which he treated—1. Of the power of intercommunication among ants; 2. Their organs of sense; 3. Their affection or regard for one another. The results are chiefly negative, contradicting many generally-received opinions. To test the ants' power of communicating information to one another, the author had a glass box for the "nest," so that he could watch what was done inside. This was placed on a pole. On the other side of the pole was a board intended as a promenade for the ants. Near to this were three pieces of glass, connected with the board by strips of paper. On one of the pieces of glass was placed a collection of food, and on the other two there was nothing. Two ants were taken and marked with spots of color, as in former observations, so that they should be readily recognized. These were both taken, one after the other, to the store of food, and were guided and taught their way to the nest. They soon learned their way to and from the nest to the food-supply, coming out of the door along the outside to the pole, around that, across the board, along the paper bridge, and so to the glass that supported the food, and so back again to the nest. Sir John Lubbock's object was to watch whether the other ants in the nest would find out the food, and, if so, to teat as far as possible whether they found it from information given, or whether they tracked the scent. He devoted certain periods to watching the movements of the ants, counting the number of journeys made by his marked ants, and also recording how many untaught strangers made their way from the board along the right bridge to the food. At his first period of observation he found that, while his marked ants made forty journeys with food, nineteen strangers also came on to the bridges. Of these, two only turned to the food, eight turned to the wrong bridge, and the rest went, straight on. Modifications in the arrangements of the bridges were made in different ways, while the rest of the construction was left unaltered. The observations made on different days and during periods of different duration all showed the same result.
In referring to the organs of sense, Sir John had endeavored to ascertain whether the antennæ are organs of hearing or of smell. He had tried them with all sorts of noises he could contrive, and found no results. If ants have hearing, they must be sensible to those vibrations of the air which do not affect the human ear. But he had also tried the antennæ with smells, and he found that if he put a fine camel's-hair pencil with a scent on it near one of them it shrank away, and then, if applied to the other, that also turned away. The use of the antennas, however, still needs investigation, and Sir John hopes soon to make further observations. As regards their affection for one another, he does not doubt that an ant that dies laden with food will be cared for by its companions; but he brought forward a number of instances in which he had put ants that had suffered immersion in water for periods of from an hour to ten hours in the way of ants that were passing by, and he found almost invariably that they took no notice of their unfortunate brethren. Indeed, the exceptions in which any attention was paid were so few that Sir John said he was disposed to regard these as ants with individual feelings, which were by no means those common to the community. It, is understood that the results of Sir John Lubbock's long-continued researches into the habits of bees and ants will be given to the public before long in a volume of the "International Scientific Series."
Sea-Soundings without a Line.—Dr. Siemens exhibited, at a recent meeting of the London Royal Society, an instrument devised by himself for ascertaining the depth of the sea. In explaining the principle of this instrument, Mr. Siemens observed that the total gravitation of the earth, as measured on its normal surface, is composed of the separate attractions of its parts, and that the attractive influence of each equal volume varies directly as its density and inversely as the square of its distance from the point of measurement. The density of sea-water being about 1.026, and that of the solid constituents composing the earth's crust about 2.763, it follows that an intervening depth of sea-water must exercise a sensible influence upon total gravitation if measured on the surface of the sea. His instrument, which he calls a bathometer, is described in the London Times as consisting "essentially of a vertical column of mercury, contained in a steel tube having cup-like extensions at both extremities, so as to increase the terminal area of the mercury. The lower cup is closed by means of a corrugated diaphragm of thin steel plate, and the weight of the column of mercury is balanced in the centre of the diaphragm by the elastic force derived from two carefully-tempered spiral steel springs of the same length as the mercury-column. One of the peculiarities of this mechanical arrangement is, that it is parathermal, the diminishing elastic force of the springs with rise of temperature being compensated by a similar decrease of potential of the mercury-column, which decrease depends upon the proportions given to the areas of the steel tube and its cup-like extensions."
The instrument is suspended in such a manner as to retain the vertical position, notwithstanding the motion of the ship, and the vertical oscillations of the mercury are almost entirely prevented by a local contraction of the mercury-column to a very small orifice. The reading of the instrument is effected by means of electrical contact, which is established between the end of a micrometer-screw and the centre of the elastic diaphragm. The pitch of the screw and the divisions in the rim are so proportioned that each division represents the diminution of gravity due to one fathom of depth. Actual experiment has shown the apparatus to be very reliable.
Formation of Mountain-Chains.—This subject is considered by Prof. Joseph Le Conte in the April number of the American Journal of Science, in which interesting facts are presented, the results of observations made by the author in the Coast Range of California. He finds that the actual length of the folded strata is about two and a half to three times the horizontal distance through the mountains. It thus appears that from fifteen to eighteen miles of strata, that is, of original sea-bottom, has been crushed or mashed into six miles, with "corresponding up-swelling of the whole mass."
This diminution of distance, according to the theory of Prof. Le Conte, has not arisen from folding of the strata, but by mashing of them by horizontal pressure.
From the flattened and elongated form of little nodules of clay found in some of the strata, he concludes that their elongation vertically exactly correlates their shortening horizontally, and that the one is to the other as two and a half or three is to one. It thus appears that in the compression of the beds their constituent particles underwent a change of form corresponding with the conditions of the pressure.
These clay pellets or nodules are supposed to have been formed on the bottom of gently-flowing streams, are a part of the original sedimentary beds, and are the same in character as those which form greenish spots in slate, as described by Prof. Tyndall.
It will be seen that, in accounting for the elevation of mountain-chains, Prof. Le Conte differs from Prof. Dana in this: that while they agree that mountain-chains are formed by yielding of the earth's crust, Prof. Dana attaches importance chiefly to the bending and plication of it, Prof. Le Conte to the crushing of it. He says, "I am satisfied that Prof. Dana greatly underestimates the amount of elevation by simple mashing as compared with folding."
Brain-Weight and Mental Power.—Great weight of brain is commonly regarded as evidence of great cerebral power. That this conclusion, however, is erroneous, is shown by Dr. Robert Lawson, who, in the Lancet, compares the brain-weights of some of the great men of modern times with the brain-weights of lunatics who died in the West Riding Asylum. He gives the following instructive table:
|Brain-weight of||Dr. Chalmers||53||Lunatic||58|
|"||Sir J. Y. Simpson||54||"||58.5|
It will be observed that only Abercrombie and Cuvier surpass in weight of brain the inmates of the asylum. One of these lunatics, he whose brain weighed 61 ounces, was seventy-one years of age when he died; when he was forty-five, his brain probably weighed not less than 64 ounces, thus equaling in weight the brain of the great Cuvier, and exceeding that of Daniel Webster by 20 per cent. From all this it follows that great weight of brain is not in itself a conclusive evidence of great intellect.
From this comparison of brain-weights, Dr. Lawson passes to the consideration of the relations between genius and insanity. "Every day," he says, "the observation of the poet, that great wit is nearly allied to madness, gains a wider and more practical acceptance. So much is this the case that Dr. Wilks ventures to make the statement that it is probably the insane element which imparts what we call genius to the human race, the true celestial fire. And though it is fearful to think of the propagation of a race tainted with insanity, yet it does not follow that an infusion of the insane blood may not be desirable. Dr. Maudsley holds the same opinion."
Preservation of Zoölogical Specimens.—Last summer, Profs. Verrill and Rice, of Yale College, made a number of experiments to ascertain the effects of various chemical preparations upon marine invertebrates, the objects being to improve existing methods of preserving specimens and to ascertain the best means of killing in an expanded state species which ordinarily contract very much when put directly into alcohol. The results are given in the American Journal of Science, by Prof. Verrill, who says that several very fine preparations of Actiniæ in a state of nearly perfect expansion were made by slowly adding a concentrated solution of picric acid to a small quantity of seawater in which they had been allowed to expand. When fairly dead, they were transferred to a pure saturated solution of the acid, and allowed to remain from one to three hours. They were then placed in alcohol for permanent preservation. The alcohol should be renewed after a day or two, and this should be repeated until all the water has been absorbed from the specimen. Hydroids and most kinds of jelly-fishes can be easily preserved in the same way. Even delicate Ctenophoræ can be thus preserved so as to make fair specimens. The experiments were made with the view of finding some poison that will kill mollusks, especially gasteropods, in a fully-extended state, but the results were negative; at least no method was discovered that is more generally successful than that of allowing them to suffocate in stale sea-water, through excess of carbonic acid and deficiency of oxygen.
Improvement of the Steam-Engine.—In giving testimony before the Government Commissioners on the Advancement of Science in Great Britain, Mr. Anderson, superintendent of machinery at Woolwich, spoke of Joule's experiments on the conservation of energy as of immense value and as being an example of what government should do for the common good. Joule had made engineers thoroughly dissatisfied with their present knowledge as to what they can do with steam. "I believe," he continued, "that what Joule did will do more for this country than even what James Watt did. The part that James Walt took was very great, and the world gives him full credit for it; but the world is scarcely willing to give credit to Joule. Engineers know that the best steam-engine is not doing one-sixth of the work which it ought to do and can do. That is a sad state of matters to be in when we know that we are so far wrong, but yet no one will go to the trouble of going to the end of the question so as to improve the steam-engine as it might be done."
Underground Forests in the Thames Valley.—An interesting geological discovery, as we learn from Nature, was recently made during excavations for a new tidal basin at the Surrey Commercial Docks, London. On penetrating some six feet below the surface, the workmen everywhere came across a subterranean forest-bed, consisting of peat with trunks of trees, for the most part still standing erect. All are of species still inhabiting Britain; the oak, alder, and willow, are apparently most abundant. The trees are not mineralized, but retain their vegetable character, except that they are thoroughly saturated with water. In the peat are found bones of the great fossil ox. Fresh-water shells are also found. No doubt is entertained that the bed thus exposed is a continuation of the old buried forest which has been brought to light at various other localities on both sides of the Thames. In each ease the forest-bed is found buried beneath the marsh-clay, showing that the land has sunk below the tidal level since the forest flourished.
The Medication of Infants.—From experiments made by Dr. Lewald it appears that sundry medicines are most advantageously introduced into the system of an infant through the mother's milk. Thus of iron a larger quantity can be administered to the infant in this way than by any other means. Bismuth, however, is eliminated in the milk only in very small quantity. Iodine does not appear in the milk until ninety-six hours after taking it; iodide of potassium appears four hours after ingestion, and continues to be eliminated for eleven days. Arsenic appears in the milk at the end of seventeen hours, and continues for at least forty hours. Oxide of zinc, though one of the most insoluble preparations, is eliminated by the milk; it disappears sooner than iron. The elimination of antimony is an undeniable fact, and it is well to bear this in mind during the period of nursing; the same holds true in regard to mercurial preparations. That alcohol and narcotics are eliminated by the milk has not been demonstrated. Sulphate of quinine is eliminated very easily, and a child suffering from intermittent fever was cured by administering quinine to the nurse.