Popular Science Monthly/Volume 1/June 1872/Miscellany

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Popular Science Monthly Volume 1 June 1872  (1872) 
Miscellany
 

MISCELLANY.

CONCERNING ATOMS.

Dr. S. D. Tillman publishes in the American Chemist an able paper on "Atoms and Molecules," in which he reviews the present state of the question, and gives the reasons why we should still hold by the atom, notwithstanding the attempts made to get rid of it. Both sides of the question were early taken, on purely speculative grounds. The ancient philosophers, in their subtle reasonings on the constitution of Nature, asserted the existence of ultimate indestructible material atoms. Others, and notably Boscovich, at a later day denied the material atoms, and substituted for them what he termed centres of force. Modern chemistry, however, approached the subject from a different point of view. It was proved that the interior changes and reactions of matter are governed by definite mathematical laws, and it was inferred that material substances must therefore be made up of ultimate material units. The assumption was made, because it best explained the laws of chemical change. Still the tendency to resolve matter into force continues with many, who of course abandon the conception of atoms, and the theory that implies them.

Dr. Tillman shows that the facts of invariable weight which experiment establishes, of equal or multiple gaseous volumes, of specific capacities for heat, of the equilibrium of chemical forces, of isomeric transformations, and of uniformity, homogeneity, and constancy of structure, in the constitution of material substances, are all explicable only by the conception of indivisible and indestructible atoms.

 
WHAT BECOMES OF COMETS!

Prof. G. B. Donati, whose name is already famous in connection with comets, has just issued a paper on this subject from the Royal Observatory of Florence, which appeared in the Evening Post in full, and of which the following is the substance: He denies that any astronomer has recently seen a large comet, and affirms that none at all are visible at the present time. As for new comets, no astronomer can tell whether they will or will not appear. As to periodical comets, that of Biela, which completes its circuit round the sun in six years and nine months?, is due next August. The earth and the comet of Biela travel different ways, and their paths cross each other at a certain point. A collision is, therefore, not impossible. The comet and the earth have, however, hitherto passed the point in question at very different periods. Should Biela's comet arrive, it would traverse the terrestrial orbit on August 26th; but on that day the earth would be distant from the comet almost half as far again as it is distant from the sun. As to whether any other comet may encounter the earth, Prof. Donati holds it to be possible, but infinitely improbable. "The comets," he says, "have masses so small that, if one of them were to approach to within even a short distance from the earth, the latter perhaps would have nothing to fear, and, in all probability, in such an event, the comet would become a satellite of the earth." As for the comet of Biela, he says there is great probability that it no longer exists; although it should appear every six years and nine months, it has not been seen since 1852. From 1826, the time of its discovery, to 1852, it appeared regularly. In 1846 the comet presented a most extraordinary appearance. Instead of appearing single, as was the case on all preceding occasions, it appeared double—that is, composed of two parts, separated by a distance of more than 100,000 miles. When it appeared in 1852, the separation was still more complete, the interval amounting to 1,200,000 miles. Its non-appearance in 1858 was attributed by some to its immersion in the solar rays; but in 1866 it should have reappeared in a position so far from the sun, that it would have been visible at night; but it was impossible to discover it. Nor is the comet of Biela the only one which has failed to appear when due. That discovered by Prof. De Vico at Rome in 1814, and which should return every five and a half years, has never since been seen. What becomes of them? Kepler held that they may be dissipated, and said that as the silk-worm consumes itself while spinning its cocoon, so comets may consume themselves, and die while generating their long, interminable tails; and Newton thought that they might fall directly into the sun. But Donati conjectures that the material of Biela's comet has already fallen in part, and is still falling upon our planet. Prof. Schiaparelli, who has just got the gold medal of the London Astronomical Society for his study of comets, maintains that they are resolved into shooting-stars—meteors which traverse the earth's atmosphere. It is well known that on August 10th and November 13th many such falling stars are seen; and this is explained by supposing that the earth passes through two great belts or bracelets of meteoric matter, and draws some of the fragments or corpuscles toward itself. Prof. Schiaparelli has demonstrated that there are several comets which move round the sun, in the direction of these meteoric bracelets; and Prof. D'Arest has noticed that every year, on December 5th, shooting-stars are seen that irradiate from that part of the celestial dome in which the comet of Biela would appear, if it came at all. It seems probable that the comet of Biela forms part of a bracelet of cometic corpuscles which move round the sun. It may have here been exposed to a mechanical influence, which broke it into two parts, and it is quite possible that many other breakings may have taken place, reducing it to fragments so small as not to be visible, except as falling meteors.

 
FISH AS FOOD.

Those fish are most digestible which have least of the oily element in their composition. Rich or fatty fish are apt to disturb the stomach, and prove stimulant to the general system. Thirst and an uneasy feeling are frequently produced by them, and it is this, doubtless, that has led to the practice of drinking spirits with this class of food. Hence, the proverb, "Brandy is the Latin for fish." It is well, therefore, in selecting fish, to choose those that cook dry, and are freest from oily matter. The sooner a fish is cooked, after being taken from the water, the better it will be. There is a popular notion that, like butchers' meat, fish is improved by being kept awhile before it is fitted for the table. This is a mistake. There is a white curdy matter, plainly visible between the flakes of freshly-boiled fish, which adds much to the flavor, and is highly nutritious. This is really a film of albumen, produced by the coagulation of the serous juices, contained in the muscles. If the fish is kept long before cooking, a large share of this is lost, and the flavor of the fish correspondingly impaired. Fishermen themselves say that fish, taken directly from the net to the kettle, are as different, in flavor and nourishing properties, from fish one, two, or three days old, such as are purchased in our markets, as "chalk is from cheese."

By drying, salting, smoking, and pickling, the digestibility of fish is greatly injured, though in some cases its savory and nutritive properties may be improved. The flesh of fish is more digestible boiled than fried, and for invalids should always be cooked in this way. That of the male fish is in most cases better eating than that of the female and, in either case, it is at its greatest perfection for food at the period of the ripening of the milt or roe. After spawning-time fish appear to get out of condition, their flesh becomes soft and flabby, loses flavor has a bluish semi-transparent look after cooking, and eaten thus is sometimes productive of much evil.

If lobsters and crabs are fresh, well cooked, and eaten in reasonable quantity, they agree with most stomachs, though less digestible than fish. They sometimes, however, produce violent colic, nausea, giddiness, depression, and nettle-rash; these effects depending upon some peculiar susceptibility of particular persons. Lobsters are frequently sold insufficiently boiled, and in this state are not nearly so wholesome as when thoroughly cooked.

Of all bivalves that are eaten, oysters are the most easily digested, and the most nutritious; and they are more digestible raw than cooked. Cooking coagulates and hardens the albumen, and corrugates the fibrine, causing both to be less easily dissolved by the juices of the stomach. Raw oysters rarely disagree even with invalids or dyspeptics. Persons of a gouty habit, however, particularly if they have dyspepsia, are sometimes violently disordered by them; and they have been known to bring on convulsions when eaten by women soon after confinement.

Many of the sauces eaten with fish are very indigestible compositions, and often the fish itself is charged with ill-effects which are solely due to the sauce. Oyster-sauce is too often made so badly, that both sauce and oysters are unfit for food.

Fish is less satisfying to the appetite than meat, poultry, or game, and, as it contains a larger proportion of water, is obviously less nourishing. On the other hand, many persons pass through the season of Lent on a diet composed almost wholly of fish, without apparent diminution of strength; and whole villages may be found on the coast, where fish almost entirely takes the place of butchers' meat, the inhabitants at the same time being noted for their health and vigor.

 
TEMPERATURE OF THE BODY IN HEALTH.

In the healthy human adult, the body being at rest, and the temperature of the surrounding atmosphere about 60° Fahr., the average temperature in the axilla is 98.4°, in the rectum 99.4° and that under the tongue is intermediate, or about 98.9°. The average healthy temperature is not absolutely identical in every individual, but may vary from 97.75° to 99°. It is slightly higher in infancy and old age than in adolescents and adults. In the same individual also there are certain slight variations in the temperature consistent with health, some of which deserve to be mentioned. In the first place, there are diurnal variations of temperature constantly occurring in healthy persons, which must be kept in mind in reference to the diurnal variations so common in febrile diseases. As a rule, the daily minimum is about daybreak, or between 2 and 8 a. m. After this a rise begins, and continues until late in the afternoon, or to between 4 and 9 p. m. These daily fluctuations are somewhat greater in children than in adults; but in any case they rarely exceed 1° Fahr., and any variation in excess of this is very transient. Secondly, it is well known that muscular exercise increases the heat of the body, while repose tends to its reduction. The differences, however, resulting from this cause, are chiefly observed in the extremities. The temperature, in health, of the hands and feet, is often much below that of the trunk and internal parts. There may be a difference of 20° Fahr. or more between the temperature of the feet and that under the tongue. The effect of exercise is to raise the temperature of the extremities to that of the trunk. It produces little change—not more than an elevation of 1° Fahr. in the temperature of internal parts, as, for example, under the tongue, and even this elevation ceases on the cessation of exertion. Thirdly, the ingestion of food causes a slight rise of temperature. The effect of a full meal is to hasten the normal diurnal rise, or to postpone its fall; but the elevation of temperature resulting from food rarely amounts to 1° Fahr. Fourthly, the temperature of the human body is influenced to the extent of 1° or 2° by that of the surrounding atmosphere. Brown-Sequard found a rise of atmospheric temperature from 46.4° to 85.1° Fahr., to raise the bodily temperature from 97.9° to 100.22° Fahr. When the temperature of the atmosphere exceeds that of the normal standard of the human body, the temperature of the body occasionally exceeds the range compatible with health. It is also to be noted that young children and persons of advanced age have less power than adults of resisting external cold—the temperature of the body being more easily and considerably reduced by it in the former case than in the latter.—Murchison.

 
IMPURITIES OF WATERS.

There are certain abnormal conditions of waters, arising from natural or artificial causes, that are not very clearly understood, and which present interesting features for study and investigation. The water of Jamaica Pond, near Boston, affords a somewhat remarkable illustration of such changed condition, or sickness from natural causes, at the present time.

This pond, which is situated at a comparatively high elevation, has one small feeding-stream, and an equally small outlet; it receives no artificial drainage, and is not in a thickly-settled locality. Its water is still supplied, through pipes, to many citizens, and also to the neighboring towns of Brookline and West Roxbury. During the winter of 1866, after two seasons of drought, this water first exhibited the peculiar condition which it presents again this winter, also after two seasons of severe drought.

The water is not perfectly clear, and does not become so by standing; it is cloudy, but not colored; its color and taste are decidedly offensive, resembling water containing putrefying animal matter; these conditions are more evident when the water is heated, and are retained after evaporation to a small volume. Ordinary analysis shows the difference between the common condition of this water and its present peculiar state to be as follows: one United States gallon of each contains—

Normal Abnormal
Organic matter 1.36 grains. 2.33 grains.
Mineral matter 2.41    " 2.56    "
Total weight of impurities 3.77    " 4.89    "

By filtration, through paper, the water becomes clear and brilliant, the odor and taste of the filtered water being natural; and it is possible, in this way, to separate the offensive matter from the water and retain it for examination. This substance, which gives odor, taste, and additional weight to the impurities, consists of organized and vegetating bodies, which, as seen with the lens, are short, white threads, somewhat like conferva in form, but the threads are very short and perfectly white, differing in these respects from the green or brown confervoid growth of the summer months.

The water of this pond at present exhibits the natural balance between the animal and vegetable life below the surface, disturbed or destroyed. Crustaceous animalculæ, common in the water usually, are not to be found, while there is an extraordinary growth of subaqueous vegetation, of a low order of organized forms, emitting a repulsive odor.

The cause of this change in a large body of potable water, hitherto one of the purest, may be found in the excessive and protracted droughts of the two past seasons, modifying the growth of subaqueous vegetation, and allowing an offensive kind to predominate. And the water will, undoubtedly, recover its normal condition, with the change of seasons and an increased flow from the deep springs affording supplies to the pond, as it did in the spring of 1866 after the former disturbance.

An instance of peculiar condition, caused by artificial means, is that of the water in a manufacturer's well, yielding an abundant supply, but situated about three hundred feet below a brewery, on a hillside. In this case, after the brewery had been in operation for two years, this well-water, quite unexpectedly, developed a fungous growth of enormous size and quantity. I took from the water in the well several individual plants, which were found floating on the surface, that were each literally nearly as large as a man's head, and, in the month of August, they increased so rapidly as to close the large iron outlet pipe, having a diameter of six inches.

These fungi, when placed in a dilute alcoholic solution, in a warm room, increased in size, producing acetic acid rapidly, and were true vinegar-plants (mother); they evolved a very offensive odor when decaying, and soon rendered the well-water unfit for use. The source of the germs of these plants was traced directly to that part of the brewery where returned empty ale barrels were washed and steamed before being refilled, and where the drainage was not perfect, although the entire floor was paved with bricks laid in mortar. My attention has been called to many other cases of a similar nature, but to none where the cause and effect were so marked as in this well, the water being naturally calcareous, hard, and free from organic matter.—S. Dana Hayes, in American Chemist.

 
A MARKED MAN.

A man has lately turned up in Europe, whose attainments, both lingual and dermal, are exciting no small amount of wonder. Linguistically considered, he perhaps has numerous equals, though it is said that, besides Greek, his native tongue, he speaks Arabic and Persian fluently, French, Spanish, Italian, German, and English, with various degrees of ease and accuracy. But his other attractions are truly extraordinary, though chiefly for their showy superficiality; in which respect, after all, he doesn't differ so very much from a good many other famous people. The man is tattooed from head to foot, there not being a square inch of skin on the whole surface of his body that is not covered with tattoo-marks. His story is, that tattooing was inflicted on himself and two others in Chinese Tartary, as a punishment for acts against the government; that one of his companions died; the other was made blind, and is now living in Hong-Kong, while he had succeeded in making his escape. The man has a fine physique, and, stripped, appears as if his whole body were closely enveloped in a richly-woven web of Turkish stuff. Closer inspection, however, resolves this appearance into a great variety of figures, mostly of plants and animals, that have been pricked into the skin in colors of blue and red. Altogether there are some 384 such figures, representing apes, leopards, cats, tigers, eagles, storks, swans, men, women, elephants, lions, crocodiles, snakes, fish, snails, fruit, leaves, flowers, etc., while on the hands are certain inscriptions, said by Prof. Miller to belong to the language of Burmah. The marking appears to have been done with the juices of plants, as there are no traces of enlarged lymphatics, such as are often produced when tattooing is done with pulverized charcoal, or gunpowder. Then the instrument with which this man was tattooed, and which he brought away with him, is split like a steel pen at the tip, so that fluid substances could easily be taken up by it.

 
CONSANGUINEOUS MARRIAGES AND IDIOCY.

Dr. Mitchell, of the Edinburgh College of Physicians, says of idiocy and its relations to marriages of consanguinity, that in more than sixty per cent, of the cases of idiocy occurring in the British Isles the condition is acquired, not congenital, and is due to one or other of the numerous accidents to which children are liable. He disapproves of unions of near relations, but states that proof is wanting that any evil resulting from them is dependent on a mysterious influence intrinsic in the consanguinity itself. His objections to marriages of blood-relations proceed rather from a consideration of the increased risk in such unions of the transmission of morbid peculiarities. Thus, if a deaf-mute is married to a person in possession of the faculties of speech and hearing, the chances of having a deaf-mute child will be as 1 to 135; but, if deaf-mutes intermarry, the chances of having a deaf-mute child rise to 1 in 20.

Speaking of the causes which produce idiocy after birth, Dr. Mitchell points out that purely intellectual exercise, in excess, is more detrimental to children than purely emotional exercise in excess, but the reverse holds true in the case of adults. In children as well as in grown-up persons, disorder of the moral faculty, as a rule, precedes intellectual disorder, and overteaching of pupils is first apparent in change of character. Prolific causes of idiocy are scarlet fever, whooping-cough, and measles, diseases to which thirty per cent, of all the idiots and imbeciles in Great Britain are due.

 
TESTS OF IMPURE WATER.

In its provisions for securing to consumers a sufficient supply of pure water, the public health bill, now before the English Parliament, thus defines what will be considered as polluting liquids:

1. Any liquid containing in suspension more than three parts by weight of dry mineral matter, or one part by weight of dry organic matter, in 100,000 parts by weight of the liquid.

2. Any liquid containing in solution more than two parts by weight of organic carbon, 1, or .03 by weight of organic nitrogen, in 100,000 parts by weight of the liquid.

3. Any liquid which exhibits by daylight a distinct color, when a stratum of it 1 inch deep is placed in a white porcelain or earthenware vessel.

4. Any liquid which contains a solution, in 100,000 parts by weight, more than two parts by weight of any metal except calcium, magnesium, potassium, and sodium.

5. Any liquid which, in 100,000 parts by weight, contains, whether in solution or suspension, in chemical combination or otherwise, more than .05 part by weight of metallic arsenic.

6. Any liquid which, after acidification with sulphuric acid, contains, in 100,000 parts by weight, more than one part by weight of free chlorine.

7. Any liquid which contains, in 100,000 parts by weight, more than one part by weight of sulphur, in the condition either of sulphuretted hydrogen or of a soluble sulphuret.

8. Any liquid possessing an acidity greater than that which is produced by adding two parts by weight of real muriatic acid to 1,000 parts by weight of distilled water; or—

9. Any liquid possessing an alkalinity greater than that produced by adding one part by weight of dry caustic soda to 1,000 parts by weight of distilled water.

 
PERMANENT PHOTOGRAPHS

The difficulty with photographs is, that they fade; the desideratum is to give them stability. Mr. W. H. Sherman, of Milwaukee, has been experimenting for some time past with a view to this object, and claims to have reached the result sought. The object was to introduce an unchangeable pigment of some kind into the print by deposition from solution, and he succeeds with the bisulphide of mercury (vermilion). The process and its explanation are as follows: "A solution is prepared, composed of hyposulphite of soda and a mercurial compound in such proportions that the bisulphide of mercury is slowly deposited, the deposition being almost entirely suspended until the print containing the unreduced chloride of silver is added to the solution. The withdrawal of hyposulphite to dissolve the chloride causes the deposition of the bisulphide to take place in the print." Pictures obtained in this manner resist strong reagents in a way that gives promise of great permanence, while they have a rich tone, and a novel and fine effect. Mr. Sherman has been experimenting a good deal on the precipitation of vermilion, and finds the color of the product powerfully affected by light.

 
THE SUN'S ATMOSPHERE.

Dr. Janssen, the French astronomer, in a letter to Prof. Newton, of Yale College, an extract from which is published in the American Journal of Science and Arts, says of the sun's atmosphere: "My observations prove that, independently of the cosmical matter which should be found near the sun, there exists about the body an atmosphere of great extent, exceedingly rare, and with a hydrogen base. This atmosphere, which doubtless forms the last gaseous envelope of the sun, is fed from the matter of the protuberances which is shot up with great violence from the interior of the photosphere. But it is distinguished from the chromosphere and the protuberances by a much smaller density, a lower temperature, and perhaps by the presence of certain different gases." Janssen proposes to call this the "coronal atmosphere," as he considers it to produce a large portion of the phenomena of the solar corona.

 
SCIENTIFIC ADVANCE IN GERMANY.

Prof. Virchow, in his address before the Congress of German Naturalists, states some facts which show what progress freedom of discussion has made in Germany since the beginning of the present century. "Not perhaps at the dead of night, but still beneath the veil of secrecy, a handful of savants assembled for the first time at Leipsic, at the invitation of Oken. In fact, in 1822, no considerable body of men could come together in Germany, in answer to a public invitation, with the permission of the civil authority. They could not discuss among themselves scientific questions, no matter how unconnected with the political and national questions of the day. Add to this that other fact, that, if I am not mistaken, it was only in 1861, at the Congress of Naturalists at Spires, that the names of the Austrian members could be made public, and then we can appreciate the tremendous change that has been brought about in Vaterland." In the same address Dr. Virchow pays a well-earned tribute of honor to French savants. He opposes also the suggestion that has been made by certain German professors, that brevets, or honorary memberships of French Academies, etc., held by German scientific men, should be sent back, for the reason that a distinguished French botanist had recently declined the honor of being made an associate of the Natural Science Academy of Leipsic.

 
ACTION OF SEWAGE-GAS ON LEAD PIPES.

Dr. Andrew Fergus states that lead soil-pipes are often found corroded and even perforated in positions which justify the belief that the destructive agent is sewer-gas. The corroding action always takes place from within, and is generally confined to the upper surface of the pipe most frequently in those situations where it lies in an horizontal position, though vertical pipes and the upper surfaces of bends are sometimes affected. Among the diseases he has observed as resulting from this state of things, typhoid fever, diphtheria, scarlet fever, and diarrhoea, are mentioned.

 
COOLING AND VENTILATION OF RAILWAY-CARRIAGES.

An ingenious contrivance for excluding dust and cooling the air of railway-carriages in hot countries is described in a late number of Engineering. It consists of an arrangement attached to the under side of the carriage, into which air is admitted and made to pass between layers of material that are kept constantly wet by a supply of water from above, and that present a large evaporating surface. By this means all dust is arrested in the chamber, and the air cooled before it enters the interior of the carriage. The windows of the car are so arranged that thorough ventilation is secured and the accumulation of moisture prevented. The appliance is now in use on several railways in India, and is found to be of great value. The average reduction of temperature secured by it is about 15° Fahr., with an evaporation of six gallons of water per hour. With a larger amount of water it is said that a reduction of 30° may be readily obtained.

 
CONSCIOUSNESS AFTER DECAPITATION.

M. Heindrich, who filled the office of headsman in Paris for fifty-four years, has lately died, after officially cutting off the heads of 139 criminals. He appears to have been a man of some cultivation; and had sufficient interest in his business, it is said, to attend the lectures of Velpeau, in order to obtain a knowledge of the exact position of the "vital joint." He also made various improvements in the construction of the guillotine. A visitor once asked him if he thought the separated head retained consciousness after it had fallen into the basket. Without giving a direct reply, he related several instances which went to support an affirmative answer. On one occasion he said a woman's head made a faint effort to spit at him; and he also spoke of violent contortions occurring in the muscles of Orsini's face—a phenomenon that has been observed in the faces of others immediately after decapitation. It is the opinion of the Lancet that these movements are reflex, and not at all of a conscious nature. They are probably due to the sudden loss of a large amount of blood, which here, as elsewhere, gives rise to convulsions. The mere blow must stun, and, before recovery takes place, the flow of blood from so many large vessels would be sufficient to produce perfect unconsciousness.

 
FOSSIL FLOWERS AND INSECTS.

A fauna and flora of the Eocene period have been dug out of the rocks by M. Munier-Chalmar, of the French Geological Society. He exhibited before it crustacea, insects, and flowers, in a wonderful state of preservation. The minutest details of the delicate organization of these vegetable and animal species are preserved with great nicety and fidelity. The flowers retain their calix and corolla, and some of the stamens still have their anthers. M. Munier exhibited some which are yet buds, others just blown, and still others with their petals all gone, and nothing left but the ovary. We may still observe the soft appearance of the insect larvæ, and can even discern the nerves of the budding wings of the nymphæ. Among the insects M. Munier recognizes a familiar domestic bug, in which may be seen the glands which secrete the mal-odorous liquid peculiar to those insects. Finally, among the Crustacea, he has found a new species, in which we may study the minutest details of the masticatory apparatus.

 
A PHOSPHORUS-LAMP.

The following is a description of a safety-lamp, employed by the watchmen of Paris, in all magazines where explosive material is stored: An oblong phial of the whitest and clearest glass, containing a piece of phosphorus about the size of a pea. Pour in some olive-oil, heated to the boiling- point, until the phial is two-thirds full, and then seal it up hermetically. To use it, remove the cork, allowing the air to enter the phial, and then recork it. The whole empty space in the bottle will then become luminous, and the light obtained will be equal to that of a feeble lamp. As soon as the light grows weak, its power can be increased by uncorking the phial, and allowing a fresh supply of air to enter. Thus prepared, the phial may be used for six months.

 
EFFECTS OF TRAINING.

The Lancet, in a short article on "training and its risks," à propos of the recent university boat-race, says: "We could mention numerous cases in which the reserve force of the system has been so forestalled by amateur oarsmen that not only specific vascular disease, but physical decrepitude, has declared itself long before the meridian of life. Within the last few days we have seen a list of cases in which, besides premature ill-health, even death itself was induced by the constant practice of rowing, followed by the tremendous final struggle. It is not only that the transition from customary to athletic regimen, and vice versa, has evils of its own, even in the case of professional watermen, but such evils are aggravated for the university amateur, who has so often to proceed from hard rowing to hard reading."

 
PHYSIOLOGICAL ACTION OF CAFFEINE.

According to Prof. Aubert's estimate, roasted coffee contains only about one-fourth per cent, caffeine; and, if so, it is not easy to account for the exciting effect of the infusion. The action of caffeine upon the spinal cord is analogous to that of strychnine, but far weaker. It notably augments palpitation of the heart. Artificial respiration arrests its mortal effects. Caffeine also produces transitory paralysis of the pneumogastric nerve. Dr. Nasse supposes that the action of the infusion of coffee is to be attributed, not to the caffeine alone, but to empyreumatic matter.

 
THE DEEPEST WELL.

The Germans claim the deepest hole that has ever yet been bored into the earth. It is situated near a small village about twenty-five miles from Berlin. The boring was commenced in 1867, and stopped last year, at a depth of 4,170 feet. The diameter of the hole at the top is 15½ inches. For the first 281 feet the drill passed through solid gypsum, when a bed of quite pure rock-salt was struck, the under side of which had not been reached when the boring ceased. Careful observations of the temperature at various depths are now being made, which will be placed before the public when completed.

 
PHYSICAL CONDITION OF CENTENARIANS.

In a paper lately read before the London Anthropological Society on the physical condition of centenarians, Sir Duncan Gibb gives an interesting account of the examination of six persons who had severally reached the age of one hundred years. He found the organs of circulation and respiration in a condition more approaching to the prime of life than old age. None of those changes which usually mark the age of seventy were observed; and, in nearly all, the special senses were unimpaired, and the intelligence perfect, which shows at least tie complete integrity of the nervous system.

 
ARROW-HEADS IN NEW JERSEY.

Dr. Charles G. Abbott, writing in the American Naturalist on the "Stone Age in New Jersey," states that stone arrow-points of every variety are found at numerous points throughout the State, and that a reference to the drawings of arrow-points in Nilsson's "Stone Age in Scandanavia," and Lubbock's "Prehistoric Times," shows that whatever they have illustrated, either from the north of Europe or Terra del Fuego, is also to be met with in New Jersey. These arrow-heads are shaped from a great, variety of minerals, but those made of various forms of quartz are the most abundant.

 
HONORS TO PROF. DANA.

At the meeting of the Geological Society of London, for February 16th, the president, Mr. Joseph Prestwich, presented for transmission to Prof. Dana, of New Haven, what is regarded as the highest honor the Society can confer, namely, the Wollaston gold medal, which had previously been voted by the council to this distinguished scientist. Prof. Dana's labors were spoken of in the highest terms; his numerous important contributions to almost every branch of geological science being characterized as remarkable, both for learning and skill of presentation.

 
COPPER IN ORGANIZED STRUCTURES.

Besides its wide-spread diffusion in the inorganic world, copper is also a frequent constituent of plants and animals. It is almost constantly found in flour, straw, hay, meat, eggs, cheese, and other articles of food, and also in sea-weed. In the animal kingdom, it occurs in the blood of certain mollusks and crustaceans, and is likewise found in the blood and tissues of many of the higher animals—in proportionally large quantity in the liver and kidneys.

M. Duclaux has lately discovered it in cacao-beans. The proportion is greatest in the outer covering or husk, although the inner parts, of which chocolate is made, also contain a notable quantity. Dr. Craig, of the Army Medical Museum, Washington, has quite recently found traces of copper in oysters; not in sufficient amount, however, to account for the green color which they sometimes present.

MAGNETIC VARIATIONS.

The last word about solar influence is uttered by Carl Hornstein, of Prague, who, summing up the results of an immense number of observations, says that the variations of each of the three elements of terrestrial magnetic force, declination, inclination, and horizontal intensity, have a period of about 26⅓ days. This periodicity can hardly be explained, except by the influence of the sun.

 
COLD IN GERMINATION.

The cold of winter is said by M. Duclaux, of the Paris Academy of Sciences, to be necessary for the germination of certain vegetable grains, and for hatching the eggs of the silk-worm. His researches in this matter he proposes to continue and to extend, so that the effects of cold may be ascertained to the greatest possible degree of exactitude.