Popular Science Monthly/Volume 1/September 1872/Miscellany
MISCELLANY.
Experiments on the Solar Spectrum.—Some experiments recently published by Dr. John W. Draper, of the New York University, on the heat of different portions of the solar spectrum, will change, in several important particulars, the views hitherto held on that subject.
Until now, it has been supposed that the heat of the spectrum is greatest below the red region, and that it gradually declines as the thermometer passes through the orange, yellow, green, blue, indigo, and violet, successively.
Dr. Draper shows that, while this is true as a matter of observation, the general conclusion drawn from it is altogether incorrect. In the prismatic spectrum the red and less refrangible colors are compressed together, the violet and more refrangible are expanded. This distortion is necessarily due to the action of the prism itself. But, in the diffractive spectrum, formed by lines drawn with the point of a diamond on glass, the arrangement of the colors is altogether different; they are placed according to their wave-lengths.
Dr. Draper proves that, for the correct solution of this problem of the distribution of heat, the visible spectrum alone should be employed, the ultra-red and ultra-violet invisible rays being removed. He next finds the centre of the visible spectrum, proving that it is a little beyond the sodium-line D. He then, by the aid of a silver mirror, collects all the less refrangible rays up to this centre into one focus, and all the more refrangible rays from this centre into another focus, and measures the heat of each. On the received view, the former of these foci should contain nearly all the heat, the latter little or none. In several hundred experiments in which exact measures have been made, it turns out that the heat is the same in both.
From this, some very remarkable results follow. Among them we may mention, that all the rays of the spectrum, irrespective of their color or wave-length, have equal heating-power; and that, in fact, the heat manifested in any part of the spectrum is due to the stoppage of the motion of the rays—their extinction. It is the transmutation of motion into heat.
Extensive Conglomerate Formation on Long Island.—A short distance northeast of the village of Farmingdale, on Long Island, there is an extensive formation of ferruginous conglomerate, of much geological interest, and considerable economic value. It is found in the level sandy tract which extends from near Farmingdale to some fifty miles eastward. Over this tract stones larger than good-sized pebbles are exceedingly scarce. In digging wells, it is found that pebbles and sand occur in layers, at all depths yet penetrated. The conglomerate consists simply of these sandy and gravelly layers, hardened into a compact, brown-colored mass, which can be blasted out in blocks, and which answer a very good purpose for the foundations of buildings. The thickness of the formation is thought to be about 12 feet. The rock appears to grow harder on exposure, and some specimens give out a clear, ringing sound when struck with a hammer. The sand-grains which enter into its composition are of a brown color throughout, while the pebbles are only colored externally. Compounds of iron are associated with the mass, and the waters of the district are also largely ferruginous, whence it is suggested that the formation may be due to a kind of cementing action exerted by the iron, left by the waters that have percolated through the sands.
Were the Ancient Italians Cannibals?—A somewhat remarkable discovery of human and animal remains is announced by Prof. Capellini, of Bologna, in a grotto in the island of Palmeria, the access to which is difficult and dangerous. Here he caused excavations to be made, and the result was the discovery of numerous flint and stone implements, the workmanship of which showed that they belonged to the earliest period of the stone age. Besides these wrought implements and various other objects brought into the cavern by its human occupants, he found a considerable quantity of bones of animals mingled with bones of human beings. The condition of these latter bones, he says, "would justify the inference that the grotto had been inhabited by anthropophagi, and that the Italians of that epoch were cannibals, like their contemporaries in Belgium, France, and Denmark."
"Among the human bones were found those of women, and part of the jawbone of a child some seven or eight years of age. Some of these bones were entire, others were partially calcined. In the centre of the cave it was possible to discern traces of a fireplace. Prof. Capellini says: 'Whoever has busied himself in prehistoric researches, whoever has read Spring's excellent work on the Chauvaux cavern in Belgium, and the writings of other authors on the subject of the caverns in France, will not hesitate to admit that the discoveries in the island of Palmeria prove that the Italians were, as I have said, man-eaters. For the present it will be sufficient for me to direct the attention of naturalists to the subject. The Cyclopians spoken of in the fable were probably these cannibals.'"
Coal-Lands of the Rocky Mountains.—According to "Hayden's Reports," which abound with useful information concerning the new Territories of the West, the coal-deposits of the Rocky Mountains far exceed any thing that had been hitherto suspected. Early travellers, as Lewis and Clarke, in 1800; Colonel Fremont, in 1842; Captain Stansbury, in his visit to Salt Lake, and others, had reported outcrops of coal on the slopes of these mountains, but probably none were aware either of its abundance, or the extent of country over which it is spread. Coal is found at different points in the Rocky-Mountain region over an area of some 250,000 square miles in extent, in strata which in some places are from five to thirty-five feet in thickness. Outcrops have been followed on the east flank of the mountains for more than 500 miles north and south; and if, as Hayden suggests, these are fragments of one great basin, broken only by mountain upheavals, or covered by later deposits, then the distance from east to west may be as much as 500 miles, or from the "Black Hills" to "Weber Canon." If the coal-strata were ever continuous over this vast area, the subsequent formation of mountains and valleys would leave them broken and disconnected, as they are now found to be. Yet it is the opinion of explorers, that here, as elsewhere, the deposits are in minor basins, united perhaps in places, but, as a rule, constituting separate beds, over a vast area of depression. Hayden says there is good reason to suppose that this area "extended northward far into Canada, and southward with the Cordilleras;" a supposition that, if true, would give an extent of coal-lands, in this section of the continent, much greater even than that just mentioned.
The Rocky-Mountain deposits are regarded as belonging to a much later geological age than those of Pennsylvania or of Rhode Island. While the latter belong to the Carboniferous age, the former are found chiefly in the upper Cretaceous or Chalk period, or in the so-called Tertiary; which brings the period of the Western coals nearly down to the latest geological ages.
The value of the Rocky-Mountain coals is unquestioned. From various analyses, it appears, that their volatile constituents reach about 38 per cent., while the amount of fixed carbon is estimated at about 50 per cent. Pennsylvania anthracite is much richer in fixed carbon, but the coals of Iowa, as well as some Scotch and English varieties, are considerably poorer in this respect. But, apart from their fixed value as sources of heat, the coals of this region derive an additional importance that can hardly be over-estimated, from their geographical position. In a country without timber, and far removed from other sources of fuel, they supply the first requirement for the development of its resources, and have already become the object of an extensive and thriving industry.
Lessons from a Brick.—An Austrian savant has discovered, by means of a microscope, in a brick taken from the pyramid of Dashour, many interesting particulars connected with the life of the ancient Egyptians. The brick itself is made of mud of the Nile, chopped straw, and sand, thus confirming what the Bible and Herodotus had handed down to us as the Egyptian method of brick-making. Besides these materials, the microscope has brought other things to light—the débris of river-shells, of fish, and of insects, seeds of wild and cultivated flowers, corn and barley, the field-pea, and the common flax, cultivated probably both for food and textile purposes, and the radish, with many others known to science. There were also manufactured products, such as fragments of tiles and pottery, and even small pieces of string made of flax and sheep's wool.
Zoology of the Galapagos.—A correspondent of the Tribune, accompanying the Hassler expedition, gives an interesting account of the animals observed in the Galapagos Islands. He says:
Over 50 different kinds of fishes were obtained, and of these over three-fourths are peculiar to the Galapagos. Of the Galapos, from which the islands are named, and in which they once so richly abounded, we only got a few specimens, and those very small compared with those of olden time. They have been so eagerly hunted for their flesh that they have been driven from the more accessible places, and stand a good chance of being altogether exterminated. Their brethren in the sea, the tortuga or sea-turtle, we saw in abundance, and got some very fine specimens. There are, as is tolerably well known, two other reptiles for which this archipelago is famous—two lizards, of a genus not found elsewhere, and very peculiar in their habits. The Spaniards called them iguanas, from their resemblance to that reptile in the West Indies and Central America. But they differ so much from their American cousin that they ought to have a name of their own, and if the scientific Amblyrhynchus looks too formidable, let us translate it and call the creature a Bluntnose. On Charles Island we found abundance of the crested Bluntnose climbing with great agility over the rocks near Black Beach. The creature is about 80 inches long, nearly black, the old males having a deep-red hue on the sides. It swims with great ease by its flat tail, and uses its long fingers and long nails for scrambling on the rocks, holding them, while swimming, close to the body. There is not a trace of web-footedness about them, and they make no use of the feet in swimming. They live on sea-weeds from the rocks in deep water, and their expression is mild and herbivorous, with a little clear, innocent eye. I was prepared for something hideous, and was agreeably disappointed. In another respect our experience differed from Darwin's, for we sometimes had no difficulty in frightening them into the water, and they came fearlessly swimming about the Hassler as she lay in Tagus Cove. These crested Bluntnoses we found upon all the islands. The slightly-crested Bluntnose we found only on Albemarle and Indefatigable. Its scientific name might mislead one, for its head is just as much crested as its aquatic brother's. The only differences between them, apparent at first sight, are these: The terrestrial animal is somewhat stouter, his nose is longer, his eye brighter, his tail less flattened and less crested, and his color is a dusky orange, deepening into brown on the hind-quarters. His habits of life are very different, as he does not go near the sea, but lives upon land-plants, and makes a burrow for himself in the sand and among the fragments of lava. He spreads his hind-legs flat on the ground, raises his chest to the height of his fore-legs, and then nods and winks at you in a very odd way. It looked to me very much like swallowing, and I thought it possible that the creature, with his head in that position, swallowed air like a toad, as a means of breathing—swallowing into the lungs, not into the stomach.
One of our most interesting adventures was landing in a little bay full of seals, so tame, or rather so little afraid of men, that we could tramp past groups of sleepers on the beach without awakening half of them, and without apparently frightening half of those that we did awake. They seemed to be fond of crawling under bushes just above high-water mark, and sleeping, two or three in a place, huddled close together. Under one bush lay a mother and her two cubs, so fearless that one of our officers held a piece of cracker to the old one, and she smelled it in his fingers as fearlessly as if she had been a pet dog. The cubs quarrelled with each other as to which should cuddle nearest the mother, and they all three snarled and snapped at the flies in the manner of a sleepy dog, and all this while a party of ladies and gentlemen, creatures as large as the seals, and which the seals could scarce have seen before, stood looking on within touching distance. These seals had much more length of arm, and used their arms more in the manner of a quadruped, than I had supposed any seal could do. I saw them walk on the beach with the whole chest clear of the ground, and even jump upon the sand. Their favorite gymnastic exercise, however, was to lie upon their backs and roll, in the manner of a horse. The tameness of these seals and of many of the land-birds was very surprising; the Bluntnoses were more shy than we had expected. I repeatedly put my fingers within half an inch of little yellow-birds and phoebes, and within six inches of mocking-birds. On James Island the birds were so numerous and so tame that, while I was trying the experiment whether whistling to a yellow-bird would divert his attention so much as to make him allow me to touch him, six other birds—including two mocking-birds—came up and alighted on twigs within two yards of the yellow-bird to see what was going on between us. As for the flies, their tameness and pertinacity of adhesion, at the Galapagos, goes far beyond all travellers' accounts. I knew a good house-keeper In New England who affirmed that house-flies could not be driven out of a room unless you struck and killed one or two, in order to show the others that you were in earnest. You cannot drive the Galapagos flies from you even with that expedient. The birds and seals are not frightened by being stoned or shot; they don't know what stones and guns mean, and the flies are not frightened or discouraged by having any amount of their comrades killed. When a boat was coming off-shore, the usual occupation, in order to prevent carrying the nuisances on ship, was for everybody to be picking the flies off themselves (almost as they would burrs), killing them, and throwing them into the water, from the time of leaving the beach to the arrival on the deck of the ship; and the last fly slaughtered before you go into the cabin is no more afraid of you than the first one you slew at the beach. They are not all biting flies; we have escaped trouble from mosquitoes and biting flies during the whole voyage, but they are crawling, tickling, adhesive, tantalizing creatures. It was pleasant to find here at the Galapagos a species of penguin, smaller and more sober in dress than our old friends of the Straits of Magellan, but with the same winning, cunning manners that made the birds in the Straits such favorites with our party. And, while speaking of the birds of these islands, I would not forget the splendid flamingoes, six feet high, of which we got many fine specimens. They sailed about in parties of 12 or 20 birds together, making long lines of scarlet flame floating through the air. We tried their flesh on the table, and found it the most delicious game, fully equal to the canvas-back, as it seemed to us. The archipelago offers at present a fine opportunity for a naturalist, who desires to make a residence here for several years, and thoroughly explore their structure, and their productions, to throw a strong light upon the great modern question of the origin of species, and the doctrines of evolution. Younger than Juan Fernandez, purely volcanic, bringing no seeds with them from the bottom of the sea, not having had time to alter and. amend species introduced from the main-land, how did these islands come in possession of their peculiarly-organized beings—their Bluntnoses, for example? This was the question constantly recurring to me during my visit to the Galapagos, as it had been at Juan Fernandez. Prof. Agassiz gave us a little talk one day on our way to Panama, and discussed the same point. Expressing his warm admiration for Darwin's moral and intellectual character, and earlier scientific labors, he said that he considered his present influence on science very pernicious as favoring the habit of "filling up the wide gaps of knowledge by inaccurate and superficial hypotheses." What we need, in order to extend our knowledge of the origin of species, is not hypothesis and speculation, but a careful collation of facts, and a careful extension of our observation of facts. The hypothesis that the differences of species were produced by variations taking place in unlimited, in indefinitely long periods of time, is, at all events, strongly negatived by this occurrence of such marked peculiarities of difference from the surrounding world, in an archipelago that belongs wholly to the present geological epoch, and has not existed an indefinite time.
The Bore of cutting Leaves.—A correspondent of the Scientific American thus complains to its managers: "You do not cut your paper; you compel us, the 50,000, each to cut his own! You have this day robbed me of five minutes precious time in cutting your paper, and the 50,000 each of five minutes! This would make about 520 days of the popular eight-hour kind. Suppose it reached a year or half a year of our most inestimable time; by machinery you could cut the whole edition for $25. Can you excuse yourself? Can all the slovenly publishers of books, periodicals, and newspapers furnish any sort of apology for this wasting of priceless time, amounting to some hundreds of times your own culpability? Why, Harper's Monthly has just cost me thirteen minutes, worth to me twice the price of the magazine! What! 100 years or 500 years of human labor wasted weekly in cutting the leaves of your paper, when a few dollars' worth of work by machinery would do it greatly better, and keep your papers and books neat, genteel, and durable! Shame on your whole fraternity!"
Curious Effects of a Brain-Injury.—The recent legal contest over the will of Davis B. Lawler, of Cincinnati, involved many interesting medical and psychological questions. Mr. Lawler died at eighty-two, without issue, leaving an estate valued at $500,000. The question arose concerning his mental state at the time when certain codicils were added to his will, which gave the bulk of his property to the German relatives of his deceased wife.
In October, 1867, nearly two years before his death, Mr. Lawler had a severe fall and concussion of the brain, which was followed by loss of memory of written language, and the codicils in question were made about a month after the accident. His physician, who saw him first six months after the fall, says that he ascertained definitely on his first visit that Mr. Lawler could see printed characters, but that they conveyed no ideas to his mind. The large head-lines of the newspaper, the Cincinnati Gazette, he could not read, though he saw them perfectly. He could write his name, and yet could not tell whether what he had written was or was not his name. He could write directions about his business, but could not read the writing though it was plain enough to others. The sight of written or printed characters failed to be converted into ideas, while his power to make them seemed to imply the possession of such ideas. But such writing as he did was shown to have been done automatically. It is well known that many acts, at first acquired with great labor, by endless repetition come to be performed without will and even without consciousness. Piano-playing, dressing, winding a watch, are acts of this nature, and signing one's name may be classed with them. Herbert Spencer says: "The actions we call rational are, by long-continued repetition, rendered automatic and instinctive." He further says: "In short, many, if not most of our daily actions (actions every step of which was originally preceded by a consciousness of consequences, and was therefore rational), have, by perpetual repetition, been rendered more or less automatic. The requisite impressions being made on us, the appropriate movements follow without memory, reason, or volition coming into play." Maudsley holds that, "when an idea or mental state has been completely organized, it is revived without consciousness and takes its part automatically in our mental operations, just as an habitual movement does in our bodily activity." And again: "As it is with memory, so it is with volition, which is a physiological function of the supreme centres, and which, like memory, becomes more unconscious and automatic the more completely it is organized by repeated practice."
After his death, there was found in the brain of Mr. Lawler a globular calcareous mass half an inch in transverse diameter, so wedged into its substance as to obstruct the backward flow of the blood. There were indications that this mass had occupied a different position, and was dislodged at the time of his fall. This case confirms the growing opinion that the faculty of language is associated with the left hemisphere of the brain, and demonstrates, as far as one case can, that the posterior lobe takes part in the operations of speech and written language.
Ascent of Mount Seward.—This mountain is, with the numerous lesser peaks connected with it, the most westerly of the Adirondack range in New York. The ascent in company with a guide has recently been made, and its barometrical measurement taken by Verplanck Colvin, Esq. The ascent took two days and a part of a third. The barometric observations were laid before Prof. Hough, of the Dudley Observatory, who made the computations, and gave as the result an altitude of 4,462 feet. Mr. Colvin speaks of the wanton waste by fire of the woods, and the consequent diminution of the rivers, and recommends to the State government the creation of an Adirondack park, or timber preserve, suggesting that the officers necessary for its care might be supported by a per-capita tax upon sportsmen, artists, and tourists a tax which he says they would willingly pay if the game should be protected from unlawful slaughter, and the grand primeval forest be saved from ruthless desolation.
A Four-legged Fish.—The members of the Australian Eclipse Expedition, if they were unsuccessful in the primary object of their voyage, saw some strange things along the shores to the north of the great Continent of Australia. Mr. Foord tells a wonderful story, "amply attested by witnesses," A a fish with four hands. This extraordinary creature was found crawling on a piece of coral dredged up from the bottom of the sea. "The body was that of a fish," says Mr. Foord, before the Royal Society on January 22d, "but, wonderful to relate, it had in the place of fins four legs, terminated by what you might call hands, by means of which it made its way rapidly over the coral reef. When placed on the skylight of the steamer, the fish stood up on its legs, a sight to behold. It was small, and something like a lizard, but with the body of a fish." It is to be hoped that a full and scientific description of this latest marvel of deep-sea dredging may soon be published, as the specimen appears to have been brought back to Melbourne. Mr. White, too, of the same expedition, tells strange tales about the rats. "The little island," he said, "upon which we pitched our tent was overrun with them, and what was most extraordinary, they were of every color, from black to yellow, and some tortoise-shell."—Nature.
Fungi in Cow's-Milk.—On this subject, Prof. Law, of Cornell University, makes a communication to The Lens for July. He says the presence of living organisms in milk has been recognized by various observers. In milk of an abnormally blue color, cryptogams and swarms of infusoria have been noticed, and kindred objects have been seen in milk of a yellow and greenish tint. Dr. Percy's "Report to the New York Academy of Medicine, in 1858, 'On Swill Milk,' shows the presence of spores in such milk when drawn, and the growth of mycelium within twenty-four hours thereafter, though the liquid had stood in a well-corked bottle in the interval. This report shows, further, the tendency of such milk to induce severe and even fatal disorders of the digestive organs of infants, fed upon it exclusively in its fresh condition." Prof. Law examined some specimens of milk, two of which, after twelve hours' exposure, being placed under the microscope, showed an abnormal adhesiveness of the oil-globules, which had accumulated in dense masses instead of remaining apart as in healthy milk. Intermixed with the globules were dark-colored, spherical bodies of a much larger size, 'spores,' and filaments. Upon examination of the water drunk by the cows, it was found to contain numerous spores of low forms of vegetable life. The cows yielding the morbid milk appeared in health so far as appetite, rumination, pulse, breathing, and state of skin were concerned, but the temperature was higher than usual, and, on a microscopical examination of the blood, it was found to contain certain ovoid bodies of at least double the size of the ordinary blood-globules. Upon withholding the water, the impurity of the milk at once disappeared." Prof. Law says: "The chain of evidence now appeared complete. The water contained vegetable spores, which developed into a luxuriant growth of mycelium when allowed to stand, or when added to milk of known purity. The presence of similar germs in the blood was demonstrated, by microscopical examination, by the further development of the cryptogram when the blood was allowed to stand, and by the appearance of the same product in milk to which a drop of this blood had been added. The constitutional effect of its presence was slight, being manifested by a rise of temperature not exceeding 2 Fahr. The germs in question were present in the milk, and grew with great rapidity in this medium. Lastly, the disuse of the contaminated water and the administration of sulphites put an end to the affection."
Preservation of Meat.—Of the vacuum-process for the preservation of meats the Food Journal says:
| Water | 69.337 |
| Muscular fibre, coagulated albumen, etc. | 17.653 |
| Soluble organic salts | 2.790 |
| Fat | 6.710 |
| Mineral matter | 3.510 |
| ——— | |
| 100.000 | |
No. 3 was a section of cod boiled in one piece. This was an exceedingly happy specimen of food preservation. It was so firm in consistence, and so perfect in flavor, that no one would have imagined that it had not been cooked the same morning. It possessed, as one of the company remarked, that peculiar liveliness of flavor which cold fish only retains for a limited period after cooking.
It was not thought necessary to submit either the game or fish to analysis.
Looking to the results of our experiments, we cannot but think that the method of preservation in tins has at last reached perfection in this process, for the development of which we were informed that a company has recently been formed with every prospect of success. When it gets into working-order, there is little doubt but that this meat will head the market until such time as some happy inventors can produce a reliable plan of importing raw meat from our colonies in a sound state.Scientific Associations.—The twenty-first annual meeting of the American Association for the Advancement of Science will be held at Dubuque, Iowa, commencing Wednesday, August 21st, at 10 o'clock a. m. On the evening of the same day a formal reception will be extended to the Association by United States Senator Wm. B. Allison, of the reception committee; after a response from the Association, Prof. Asa Gray, retiring president, will deliver his address, and give up the chair to his successor, Dr. J. Lawrence Smith. The British Association for the Advancement of Science will convene this year at Brighton; the first general meeting is appointed for August 14th, at 8 o'clock p. m., when Prof. Sir William Thomson, F. R. S., will resign the chair, and Dr. W. B. Carpenter, F. R. S., will assume the presidency, and deliver an address. The forty-fifth annual session of the German Society of Naturalists and Physicians will be held in Leipsic, commencing Monday, August 12th, and ending Sunday, August 18th.
Providence in Physical Affairs.—The Archbishop of York lately stated, at a meeting of the supporters of the Palestine Exploration Fund, that the progress of the human mind is from vagueness toward precision. In conformity with this tendency, it has been proposed to arrive at more precise ideas in regard to the efficacy of prayer in affecting the course of physical events. An anonymous letter, proposing a plan by which this may be done, was sent to Prof. Tyndall, who approved the suggestion, and forwarded the communication to the editor of the Contemporary Review, in which it has just been published.
The writer states that prayers are regularly offered by the Church, designed to secure preservation from pestilence, famine, and battles, the fertility of the soil, and weather suitable for the growth and preservation of vegetable products, for the protection of all that are in danger, and for the preservation of travellers and of sick persons. He proposes to test the efficacy of this influence, and to determine its degree, by a grand experiment, and selects the case of "sick persons" as best suited for his purpose. His plan is thus stated:
The following appears to me to indicate the manner of conducting the inquiry: it should be pursued on a system somewhat analogous to that which is pursued by the Faculty, when a question arises as to the value of any particular mode of treating disease. For example: a new remedy has been proposed, or is said, on high authority, to be efficacious, and, as authority does not suffice in medicine, further than to recommend a given course, and never to prescribe it, the remedy is carefully tested. Usually a hospital or a ward is assigned for the purpose. All the patients suffering from the disease to be treated are, during a certain period, divided into two classes, and all are subjected, as far as possible, to the same conditions, that single one of treatment alone excepted. The ages, sexes, and many other particulars of the patients, are taken into account, and duly noted. The one class is treated by the old system, and the other by the new remedy. When a very large number—for in large numbers only is there truth—has been thus dealt with, the results are compared, and the value of the remedy can be definitely expressed; that is, its influence above or below that of the old treatment, as the case may be, will appear in the percentage of recovery, or of other results.
Now, for the purpose of our inquiry, I do not propose to ask that one single child of man should be deprived of his participation in all that belongs to him of this vast influence. But I ask that one single ward or hospital, under the care of first-rate physicians and surgeons, containing certain numbers of patients afflicted with those diseases which have been best studied, and of which the mortality-rates are best known, whether the diseases are those which are treated by medical or by surgical remedies, should be, during a period of not less, say, than three or five years, made the object of special prayer by the whole body of the faithful, and that, at the end of that time, the mortality-rates should be compared with the past rates, and also with that of other leading hospitals, similarly well managed, during the same period. Granting that time is given, and numbers are sufficiently large, so as to insure a minimum of error from accidental disturbing causes, the experiment will be exhaustive and complete.
Alcoholic Hallucinations.—Dr. Magnan has been investigating the psychical and physiological effects of alcoholism upon the lower animals, and has described the symptoms of hallucination that followed in certain cases of prolonged alcoholic action. He had drugged certain ill-fated dogs for some time with liberal doses, and from the fifteenth day to the end of the experiment the following is what he observed:
One of the dogs remained almost unaffected by the protracted action of alcohol; he became intoxicated every day, but, once the drunkenness had disappeared, he resumed his usual habits; the other four, on the contrary, exhibited a very remarkable nervous susceptibility. They became restless—listened; the slightest noise caused them to start, whenever the door opened they hastened to cower in the most obscure corner of the hall, leaving in their way a trail of urine; they paid no attention to petting; when one came near them, they bit; if one threatened to strike them, they uttered piercing cries. A short time afterward, hallucinations occurred in two of them. As if pursued by an enemy, they barked violently, they ran wildly in every direction, the head turned back, and biting in the air. Whenever one entered, they crowded against the wall, moaning, crying, trembling in all their limbs. In the middle of the night they began sometimes to howl loudly, to utter doleful cries, and stopped only when one went in with the light.
These attacks of delirium were transient, and occurred regularly toward the end of the state of drunkenness. One of the dogs had hallucinations of a cheerful character, under the immediate influence of alcohol; he appeared affectionate whenever he began to stumble; later, on the contrary, he was indifferent—or, rather, he growled and bit.
These hallucinations, of frequent occurrence during two months of the experiment, became afterward rarer, probably on account of the ingestion of less alcohol.
The author gives the following indications of the stages of hallucination in cases of delirium tremens among men: In the first degree the patient believes he hears abusive language, provocations; he sees thieves, armed persons, animals, or else he hears the voice of his parents, of his friends who call him, who warn him of a danger, who appeal for his help, etc. Stimulated by these incitements, the patient answers, injures, quarrels, runs, rushes off, becomes furious, etc., all which acts tend to develop in him a boisterous condition, a state of mania.
In other circumstances he believes himself to be in prison, before a court of justice; he is accused of various crimes; he believes that he has committed them; he believes that his wife is unfaithful to him, that he is deceived by his friends; he is present at the funeral of his parents, etc. Under the weight of these distressing impressions, he is dull, restless, suspicious; he laments, he becomes terrified, he attempts to escape, sometimes even he meditates homicide or suicide; he presents, in a word, the aspect of a melancholic. Finally, in the most intense form, he believes himself chained at the foot of a scaffold, he has before him the bleeding corpses of his children, every thing is on fire, he is about to be swallowed up, etc. These appearances have astounded, appalled him, he remains motionless, in a complete state of stupor.
The Office of Lightning-Rods.—In his valuable little work on "Lightning-Rods, and how to construct them," Prof. John Phin thus states what the lightning-rod should do:
The function or office of the lightning-rod is twofold. In the first place, it acts as a means whereby the accumulated electricity existing in the atmosphere is silently drawn off, and allowed to pass into the earth, and thus prevent an explosion; and in the second, it acts as a path by which explosions, lightning-flashes, or disruptive discharges (as they are more properly called), may find their way to the earth freely, and thus be carried off without any danger of their acting with mechanical violence, as they are certain to do when made to pass through what are called non-conductors. Experience teaches us that, so long as a discharge of electricity passes off through a wire that is large enough to carry it safely, it does not cause any damage, or give rise to the exhibition of mechanical violence. A spark from the prime conductor of an electrical machine, if passed through a moderately fine wire, does not injure it; if passed through a thick card, it will pierce it; and, if passed through a small block of wood, it will rend it asunder. On the occasion of every thunder-storm, there is a large quantity of electricity to be conveyed from the clouds to the earth, through the air, which is in general a very poor conductor. This electricity always tends to pass by the easiest path, or, as electricians say, the line of least resistance. The resistance of any line may be lessened by various circumstances, such as the presence of hot vapors, as from chimneys, heated hay-stacks in the open field, or heated hay-mows in the barn; the existence of a line of carbonaceous matter, such as exists in a column of smoke; the presence of a tree with its leaves and sap, or of a house with its chimneys; or the fact that the air has been rendered moist by the passage of a shower of rain. So difficult is it, however, to detect the circumstances which render any particular path more easy than others, for the electricity to follow, that we are often unable to give a reason for its following a particular course, and the action of this mighty force seems to us like a mere freak. Such ideas, are, however, entirely wrong; and we may accept most implicitly the statement that the flash will always take the easiest path, and it must be our duty to determine beforehand what this path shall be, and to make it so easy and so perfect that the resistance will not cause the electricity to produce the slightest mechanical violence.