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Popular Science Monthly/Volume 1/October 1872/Miscellany

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MISCELLANY.

Bowlders of the Long Island Drift.—In a paper read before the Natural History section of the Long Island Historical Society, Mr. E. Lewis, Jr., gives an interesting account of the bowlders of the Long Island drift, treating especially of their size as compared with those of New England. On the north shore of the island, where the banks and headlands are rapidly wasted by the waves, bowlders, varying in size from a few inches to twenty feet in diameter, are thickly scattered about. Indeed, north of the central ridge of hills they are found everywhere, in some cases at an elevation of 300 feet above the sea-level. On Montauk Point, and in the neighborhood of the Hamptons, they are also abundant; and the immense deposits of sand along the southwestern shores were largely formed no doubt from bowlders and other materials of the drift, that have been ground up and deposited by the waves. This process is still going on, enormous quantities of bowlders and pebbles along the banks about Montauk being daily undermined and reduced to sand by the action of the surf. So far as observed, the bowlders are without sharp outlines, and many of them are exceedingly smooth. Those on the surface in the vicinity of Montauk have a blotched appearance, due to the presence of feldspar, and show evident traces of disintegration and decay. The excessive humidity of the air in this region is thought to contribute to this result.

Many of the bowlders are of large size, the largest being varieties of gneiss. Several have been carefully measured by Mr. Lewis. One on Strong's Neck, in Suffolk County, measures above the ground 22 by 26 feet, and is 25 feet high, giving a solid contents of about 14,000 cubic feet. At least half of this rock is believed to be below the surface. East of this are three masses of gneiss, which may have been originally one. If so, the volume of the mass could not have been less than 40,000 cubic feet; and if but two were originally united, of which there is reasonable certainty, the volume would have been about 27,000 cubic feet. Near Montauk are two masses of dark gneiss, one of which is, above the surface, 126 feet in circumference and 27 feet high, being somewhat cone-shaped. The other is about half this size. Not far from these is the finest though possibly not the largest specimen of gneiss upon the island. It is somewhat irregular in shape, compact in structure, and has a solid contents above the ground of 19,000 cubic feet. There are sections where bowlders, small and large, lie in masses that form continuous ledges.

The bowlders of Long Island, like those of New England, indicate the enormous transporting power that was concerned in their removal. Long Island lies between 40° 34' and 40° 10' north latitude, and the 39th parallel is supposed to be nearly the southern limit of the drift; and, as a rule, toward its southern limit the drift is composed of small masses of material, but the dimensions of the Long Island bowlders prove that there may be exceptions to this. The bowlders of the island and of New England appear to be similar in kind, dimensions, and distribution, and are believed by Mr. Lewis to have the same general origin. They also indicate but little diminution of the transporting power which distributed the bowlders of New England, and which so thoroughly modified its surface.

A New Entozoon from the Common Eel.—In the American Naturalist Dr. Samuel Lockwood describes a new parasite which he discovered embedded in the fat, or adipose tissue, on the entrails of the common eel. It has a proboscis which it can protrude from, or entirely retract into, its worm-like body, as into a conical sheath. This proboscis when extended is in the form of a cone, and is surrounded by rings of hooklets. At the extremity or point of this cone-like proboscis is a minute pore, which probably serves the purpose of a mouth. It is this spiny-armed organ which the animal forces by a slow motion into the fat, in and upon which it subsists. When the cone-like proboscis is withdrawn into the body of the animal, the forward end has a truncated appearance, and the entozoon is about one-eighth shorter than when the proboscis is extended. At this time the creature is less than a line in length. Dr. Lockwood has named the object Koleops anguilla. The first word, as denoting the habits of the animal, signifies sheathed-head, and the second, as denoting its habitat, is the technical name for the eel. Aside from the fact that this discovery has a general interest as an item of knowledge respecting the internal parasites of animals, it has a special interest to the helminthologist, as it makes the second genus of an order until now limited to one genus. On this point it is better to give the author's own words. Comparing this species with the Echinorhyncus gigas, long known to the student of the Entozoa, Dr. Lockwood says: "As to their ordinal relations, both are members of Owen's second class of the Entozoa, embracing the Sterelmintha or Solid Worms; and both evidently belong to Duvaine's Type IV., Acanthocephala or Spiny Heads, and to Randolph's Order IV., which bears the same name. Now, in this order there is but one genus, namely, Echinorhyncus, already mentioned; therefore we put in the order a new genus, to which we give the name Koleops, meaning sheathed-head, and species anguilla, because found in the common eel." Besides an extended description, the Naturalist gives good illustrative figures of the subject.

Insects and Flowers.—We are indebted to the report in the World for the synopsis of a paper read by Prof. C. V. Riley at the Dubuque scientific meeting, "On a New Genus in the Lepidopterous Family Tincidæ, with Remarks on the Fructification of Yucca"—one of the lily family.

Prof. Riley said that Dr. Engelmann, of St. Louis, had this year discovered that our yuccas must rely on some artificial agency for fertilization. The flowers are peculiarly constructed, so that it is impossible for the pollen to reach the stigma, it being glutinous and expelled from the anthers before the blossoms open. Prof. Riley, in investigating this subject, discovered that there was a small white moth that did the work, and he demonstrated on the black-board how marvellously the little insect was adapted to the purpose. This little moth, which he calls Pronuba yuccasella (yucca's go-between), was hitherto unknown to entomologists, and forms the type of a new genus. It is very anomalous from the fact that the female only has the basal joint of the maxillary palpus wonderfully modified into a long prehensile spined tentacle. With this tentacle, she collects the pollen and thrusts it into the stigmatic tube, and, after having thus fertilized the flower, she consigns a few eggs to the young fruit, the seeds of which her young larvas feed upon. He stated that the yucca was the only entomophilous plant known which absolutely depended for fertilization on a single species of insect, and that insect so remarkably modified for the purpose. There was a beautiful adaptation of means to an end, and a mutual interdependence between the plant and the animal. Prof. Riley then explained succinctly how, on Darwinian grounds, even this perfect adaptation was doubtless brought about by slow degrees. He alluded, in closing, to a practical phase of the subject. The plant and its fructifier are inseparable under natural conditions, and the fructifier is found in the native home of the plant. In the more northerly parts of the United States and in Europe, where our yuccas have been introduced, and are cultivated for their showy blossoms, the insect does not exist, and consequently the yuccas never produce seed in those places. The larva of pronuba eats through the yucca-capsule in which it fed, enters the ground, and hibernates there in an oval silken cocoon. In this state the insect may easily be sent by mail from one part of the world to another, and our own florists may, by introducing it, soon have the satisfaction of seeing their American yuccas produce seed, from which new plants can be grown.

This paper was extremely interesting to every one present, and those who discussed it pronounced it in every respect admirable. Dr. Asa Gray, than whom no one in the country is better able to form a sound opinion upon such a subject, complimented Prof. Riley on his discovery, and the lucidity of his explanation before the section.

Binary Stars.—The same journal gives a sketch of a paper on this subject by Prof. Daniel Kirkwood, of which the following is a summary:

At the meeting of the Royal Astronomical Society of London, on May 18, 1872, it was announced by Mr. Wilson that a discussion of all the observations of the double star Castor, from 1719 to the present time, had led to the remarkable conclusion that the components are moving in hyperbolas, and, consequently, that their mutual relations as members of a system are but temporary. The fact, if confirmed, will be regarded with great interest, and its discovery will doubtless be followed by a minute and vigilant scrutiny of other binary systems. But, while such a relation as that discovered by Mr. Wilson had not been previously suspected, its existence was certainly not altogether improbable. As the sun in his progressive motion through space compels such cometary matter as may come within the sphere of its influence to move about him in parabolas or hyperbolas, so two bodies of the same order of magnitude may be brought by their proper motions within such proximity that their mutual attraction shall cause each to move about the other in a hyperbolic orbit. Such instances, however, would seem to be exceptions to the general rule, as the motion of most binary stars is undoubtedly elliptic. (This fact has been explained in 1864 by the author on the basis of the nebular hypothesis.)

The components of Castor are of the magnitudes three and three and a half respectively. If we suppose that each before the epoch of their physical connection was the centre of a planetary system, the results of perturbation must have been extremely disastrous. The two stars were at their least distance in 1858.

This alleged discovery of a temporary physical connection between two fixed stars suggests a number of interesting inquiries. In the infinitely varied and complicated movements of the sidereal systems, different bodies may be brought into such juxtaposition as to change not only the direction of their motions, but also the orbits of their dependent planets. Some stars, at the rate of motion indicated by the spectroscope, would pass over an interval equal to that which separates us from the nearest neighboring systems in 20,000 years. In view of these facts, the conjecture of Poisson, that the temperature of the earth's surface at different epochs has depended upon the high or low temperature of the portions of space through which the solar system has passed, may not be wholly improbable.

A possible origin of binary systems is also indicated by Mr. Wilson's discovery. The cometary eccentricity of the orbits of these bodies is well known. In some cases the estimated distance between the components at the time of their periastral passage is less than half the radius of the earth's orbit. Now, if at the epoch of the first nearest approach the radius of either star's nebulous envelop was greater than the distance between the centres of the two bodies, the atmospheric resistance would tend to transform the parabola or hyperbola, in which the body was moving, into an ellipse. Each subsequent return would shorten the period, until, in the process of cooling, the stellar atmosphere had so far contracted as no longer to involve any part of its companion's.

It would be an interesting question whether some of the double stars, whose apparent distance apart has seemed too great to justify the hypothesis of a physical connection, may not afford other instances of motion, either as parabolas or hyperbolas.

School-Life and Eyesight.—In a communication to the Mechanics' Magazine, Prof. Liebreich describes the injuries to the eye incident to school-life, pointing out their causes, and the means to be adopted to avoid them. The changes in the functions of the visual organ, developed under the influence of school-life, are three in number: First, decrease of the range of vision; second, decrease of the acuteness of vision; third, decrease of the endurance of vision.

Decrease of the range, short-sightedness (myopia), is developed almost exclusively during school-life rarely afterward, and very rarely before that time. There is often an inherited predisposition to become short-sighted, and this is developed during school-life, more or less, according to certain external conditions. It is a common notion that short-sighted eyes are the most durable. This is founded on the fact that such eyes can see near objects distinctly without the aid of glasses, at an age when normal eyes require the assistance of convex lenses. But this is no proof of their durability. On the contrary, a high degree of short-sightedness is a diseased condition, caused by anatomical changes in the membranes of the eye, which involve a greater tendency to serious complication than the normal eye. Short-sightedness exerts an injurious influence on the general health by inducing the habit of stooping; and, from a national point of view, its increase is to be considered a serious evil.

Decrease of acuteness of vision (amblyopia) is a serious condition, generally the result of positive disease of the eye, which may exceptionally be induced at school. Amblyopia of one eye only, is, however, often produced by unsuitable arrangements for work, which disturb the common action of the two eyes, and weaken the eye which is excluded from use.

Decrease of endurance (asthenopia) is a frequent affection, that has destroyed many a career, prevented the development of many a fine intellect, and deprived many of the fruits of their laborious exertions. It arises principally from two causes: the first is a congenital condition, called hypermetropia, which can be corrected by convex glasses, and which cannot, therefore, be laid at the door of school-life; the second is a disturbance in the harmonious action of the muscles of the eye—a defect which is difficult to cure, and which is generally caused by unsuitable arrangements for work.

These three anomalies all arise from the same circumstances, viz., insufficient or ill arranged light, or from a wrong position during work. Where the light is insufficient, or badly arranged, we are obliged to lessen the distance between the eye and the book while reading or writing; and we must do the same if the desks and seats are not of the right shape and size, and suitably located. When the eye looks at a very near object, the accommodating apparatus, and the muscles which turn the eye, are brought into a condition of extra tension, and this is to be considered as the principal cause of short-sightedness and its increase. If the muscles of the eye are not strong enough to resist such tension for any length of time, one of the eyes is left to itself; and, while one eye is being directed on the object, the other deviates outwardly, receives false images, and its vision becomes indistinct (amblyopia). Or, perhaps, the muscles resist these difficulties for a time, become weary, and thus is induced the diminution of endurance (asthenopia).

In order to prevent these evils, the light must be sufficiently strong, and fall on the table from the left-hand side, and, as far as possible, from above. The children ought to sit straight, and not have the book nearer to the eye than ten inches at least. Besides this, the book ought to be raised 20° for writing, and about 40° for reading.

Ordinarily, minor considerations, such as the most compact disposition of the seats, or placing the pupils so that the teacher may the most readily look into their faces, govern the arrangements of the class-room, and, when any attention is paid to the matter of light, it is often to the detriment rather than the benefit of the class. For example: one of the rules laid down by the Educational Department in London, for the guidance of architects, is, that "the windows should be so placed that a full light should fall upon the faces both of the teachers and the children." Light coming from the right hand is not so good as that from the left, because the shadow of the hand falls upon that part of the paper at which we are looking. Light from behind is still worse, because the head and upper part of the body throw a shadow on the book or paper; but the light that comes from the front, and falls on the face, is by far the worst of all; for it not only defeats the object desired—illuminating the faces of the children—but is most hurtful to the eye. Instinctively desirous of avoiding the unpleasantness of the full glare, the children will assume all sorts of positions, which turn their faces from the master. In reading, they turn the head round the vertical axis, generally toward the right, in order to let the light fall on the book, which, when held straight before them, is completely in shadow; while, in writing or reading (the book being on the table), they bend their heads as low as possible, in order to shade their eyes by the projection of the forehead.

The best light for the school-room is from above; but, when this cannot be obtained, the desks should be so arranged, in connection with the windows, that the light shall fall upon the book or paper from the left.

Where light from gas or other artificial source is used for evening work, it should be made as steady as possible, and the lights so placed that they will not come opposite the eye, as in this situation they are dazzling and injurious. Ground-glass globes ought not to be used, for, though valuable in an ordinary room, where they tend to diffuse the light more equally, they give an indistinct light for work, and thus put a greater strain upon the eye. And, for the same reason, ground or ribbed glass should not be employed for the lower portions of windows, as the optical effect of such glass in that position is decidedly hurtful.

Jute.—This remarkable fibre, which formerly was only used for the coarsest purposes, has of late become invaluable. It makes a serviceable substitute for hair in chignons, and is now used extensively as a "mix" in silk. Owing to its kindly way of taking the dye, and the gloss which it sustains, a large quantity can be used in silk, and yet defy detection, except by an expert. It is, in consequence, highly desirable that it should be produced in our country, if possible. Some experiments by agriculturists are under way, which seem to promise success. Mr. F. T. D. Lacroix, of New Iberia County, Louisiana, has, on his plantation, several rows of the jute-plant, the seed of which was sent to him by the Department of Agriculture. The plants are very vigorous, and the indications are that jute will thrive in that climate. It bears some resemblance to flax in appearance, as it is said to in fibre.

A City's Waste.—Mr. Lepmann, director of the Central Trial Station, in Bavaria, speaks thus of the loss of fertilizers in Munich, a city of 177,000 inhabitants. He makes the sum of fertilizing elements wasted in the human excrements of the city for one year, 1, 857,714 pounds of nitrogen, of which the commercial value is 866,934 gulden; 611,054 pounds of phosphoric acid, value 122,210 gulden; 372,375 pounds of potash, value 49,650 gulden; total value 1,038,794 gulden, equal to about $500,000. This sum would be still further increased by adding to it the value of the humus-forming constituents of the excrements wasted. To make up for that waste, he states that the amount of guano furnished by Peru yearly for the German fields is about 1,000,000 cwt.

Mr. Lepmann states that Germany now possesses a system by which he is confident this enormous waste may be entirely prevented, called there the Tonnen (barrel) system. The city of Gratz, containing 80,000 inhabitants, has this system in use in every house, and has thus demonstrated the practicability of using it in large cities. As an illustration of the profit to be derived from human excrement when fairly tested as a fertilizer, Mr. Lepmann refers to the fact that, between the years 1850 and 1864, the price of that obtained from the barracks increased forty-five fold.

Mental Exertions governed by Law.—Prof. Heinrichs read a paper at the Dubuque scientific meeting, "On the Law of Probability as applied to the Determination of Mental Exertions." The following is a summary:

All phenomena in the physical world, exhibited by individuals of a mass subject to certain given influences, are regulated by the so-called law of probability. This has long been practically used by the various insurance companies, which employ millions of dollars a year; however uncertain the health of any given individual, the number of individuals dying each year in a mass of a hundred thousand individuals is perceptibly constant. So also the height of the stature of the individual in a greatly-varying quantity; but the number of individuals in an army having a certain definite height is very nearly constant, and determined by the law of probability. The application of this law of probability to the affairs of the individual man may be studied in the works of Quetelet. By several of our modern chemists the same law has been applied to the various chemical processes. If the laws which regulate mental work and mental phenomena are not radically different from those which we study in the physical world proper, then the law of probability ought to be equally applicable to the mental stature of man, as we long ago have found it to be applicable to the bodily stature of the same. By very careful determination of the relative grade of the individuals composing the large classes which have been instructed in the elements of physics at the State University of Iowa, the author has, during the past three years, had abundant means to test the applicability of the law of probability to mental exertions. The student's standing is determined by adding the numerical values of his credit for oral examination on the subject studied to the grade expressing his daily recitation and his practical work in the laboratory. Since these three quantities are determined independently of one another, and often by different persons (the class being instructed by the professor and two assistants), we have some guarantee against the accumulation of personal errors in this determination. Thus, in a class of sixty-seven students in the elements of physics, the following table shows the observed number of students per hundred who have obtained the standing given, also the calculated number of students who, according to the law of probability, should have obtained the same degree. It will be seen that the two numbers agree very closely:

NUMBER OF STUDENTS IN 100.

Standing. Observed. Calculated.
100 3.0 3.0
98 4.5 5.0
95 7.5 7.5
92 10.5 10.0
89 13.5 11.8
86 10.5 12.5
83 10.5 12.5
80 13.5 11.8
77 7.5 10.0
74 7.5 7.5
71 6.0 5.0
68 3.0 3.0
65 3.0 1.6

Dr. Hooker and the Kew Gardens.—The English papers have latterly had much to say of the difficulty between Dr. Hooker, Superintendent of the Kew Botanical Gardens, and Mr. Ayrton, a member of the Government, and Superintendent of Public Works. The Kew Gardens are part of an old royal park situated a few miles out of London, and have been developed to their present great extent and remarkable beauty, as well as in their scientific richness, mainly through the labors of the celebrated botanist Sir William Hooker, and of his son, Dr. Joseph Dalton Hooker, the present director. Without the genius, learning, enthusiasm, and, it may be added, the liberal pecuniary aid of these gentlemen, the Gardens would probably never have been created. They have been called into existence mainly through their agencies, and are now the pride of the nation, and are visited and enjoyed by many thousands of people each year, while they are of immense value to students as a vast scientific treasure-house of the vegetable kingdom. But Ayrton, who has control of the Public Works, in which the Kew Gardens are included, a surly, grouty, ill-mannered, and meddlesome old politician, seems to have taken every occasion to make himself disagreeable to Dr. Hooker by impertinent interference with his management, and various kinds of insulting treatment. Dr. Hooker endured it as long as he could, but his position at length became so uncomfortable that he felt himself compelled either to resign or to appeal to the government to keep its bully somewhere within the bounds of decent behavior. When the facts became known, a committee of the most eminent scientific men of England, including Lyell, Tyndall, Busk, Huxley, Darwin, and others, drew up an elaborate statement of the case, and appealed to Mr. Gladstone to check the outrageous course of Ayrton, and make it possible for Dr. Hooker to continue his relations to the establishment. This waked up the press, who were not slow to ventilate the case, and the subject was at length brought before Parliament. The effect has been that the crabbed Superintendent of Works has received a sharp and thorough public rebuke, which will probably exert a salutary influence upon his future behavior.

The Work of the Coast Survey.—We copy from the Tribune the following notices of papers which were read at the late scientific meeting:

Prof. Benjamin Pierce, Superintendent of the United States Coast Survey, gave an exceedingly interesting account of the measures taken by that Bureau with reference to stations for astronomical observations at great heights, such as Sherman, on the Rocky Mountains. Prof. Young, of Dartmouth College, was selected by Prof. Pierce as the proper astronomer to determine the best position for astronomical observations. In a higher position you get rid of absorption of light by getting rid of half the atmosphere. This problem Prof. Young was specially adapted to investigate, as his knowledge of spectrum analysis is superior to that of any other man in this country. Prof. Young reports the whole number of lines in the chromosphere seen from Sherman as 150, which is three times as great a number as have been observed before. This fact alone shows that higher points should be resorted to for astronomical observations. Telescopes will hereafter be placed at points higher than ever before—in Europe probably on the Alps. The next element of success depends upon the steadiness of the atmosphere. It can be said in reference to this, that a star has been recognized at these high altitudes as having a companion, or being a double star, not previously known as such. An observer on the Pacific coast reports to Prof. Pierce that he can see the companion of the star Polaris from a high point on the Sierra Nevada. It is well known that this is a test of great nicety, requiring the utmost purity of atmosphere. As to the character of the observations for precision, there are not yet sufficient observations to determine it. The evidence is already at hand to show that at some of these elevated points an observatory should be established. The best work in astronomy is done in the few best nights at any place, and by these alone the value of the position must be determined.

Prof. J. Lawrence Smith adverted to the extreme brilliancy of stars in those regions. West of Sherman the air is so dry that even the lips of observers crack, and their health is otherwise affected. He thought that more exact observations upon the planets and satellites would be made from those lofty points which would add as much of interest to this department of astronomy as did the recent discoveries in stellar analysis. It was resolved that Prof. Pierce should be added to the committee to press this matter of elevated astronomical stations upon the Government of the United States.

Prof. Pierce showed that the necessities of the Coast Survey extended its operations to all parts of the United States. No science could be divided and separated so as to stand alone. If one begins by measuring his town-lots, the method involves geometry and astronomy, geology and surveying, including ultimately the coast survey. To prove the paths by which vessels can best traverse the ocean, to test the best methods by which $2,000,000,000 of values shall be carried from the West to the East, from the East across the Atlantic, or from the shores of China and Japan to the Pacific coast, and thence across the country, was the business of the Coast Survey. All the United States is deeply interested in every part of this subject. Every ship that is lost by imperfectly-surveyed harbors is a loss to the whole country. A few great harbors—New York, Boston, Savannah, San Francisco—are vital points of commerce. The merchants of those cities are ever ready, by extending wharves and pushing out piers, to gain individual advantages while ruining the harbors. The Coast Survey is the bulwark against these encroachments. This matter should be in the hands of the General Government, and Congress should pass laws to prevent these injuries. If the coast survey were thorough, and maps were fully representative of ascertained facts, a pilot would scarcely be necessary, but yet never could be entirely dispensed with, especially in bad weather. The worst rocks have generally been discovered by the misfortune of striking upon them. Under such circumstances the pilot becomes a more accurate observer than the plummets of the Coast Survey. This was curiously illustrated by instances where pilots had taken out parties engaged in coast survey, and asked to have a plummet dropped at a spot apparently out at sea with nothing to guide it, and the surveying parties have found this strange instinctive knowledge of the pilot fixed the very spot of a dangerous sunken rock which could never have been found otherwise. The pilots discovered that, by putting down every rock that they knew of, they made maps that frightened the captains of vessels into employing them. Hence these practical observers have added immensely to the number of facts accumulated by the Coast Survey.

Prof. Pierce explained why he considered it unnecessary to carry out at present so thorough a survey of the Pacific as has been made of the Atlantic coast. The needs of the commerce of the coast is the standard by which the work of the survey is determined. He took occasion to mention that the Hassler Expedition was at the expense of private individuals, principally of Boston, and was not at the expense of the Government. Different States obtained the benefit of the coast survey by the determination of fixed points for their own interior topographical and geological surveys. A general geodetic connection has been effected in these observations, so that the whole United States will benefit by them; and the points will be taken so as eventually to procure a complete survey of the whole continent, passing through each State and the large cities. It is a work that may take a century. It is the hope of Prof. Pierce that this survey will not only be the best in the world, but that its details will be such that before long there will be no necessity for railroad surveys—the facts will be spread everywhere. As to the higher operations of the Coast Survey, their ultimate expression will be an accurate determination of the figure of the earth. Its actual figure as an ellipsoid of revolution is not yet actually known. It is one of an infinite number of possible figures, each nearly an ellipsoid of revolution. This question may ultimately be determined by observations on this continent. Observations here are more successful and free from local irregularities than in Asia or Europe. Yet there are some such local irregularities here—notably one near Boston, where there is some strange deviation of density from the surrounding country.

THE FEMALE THE BETTER HALF.

If there were able debaters among the members of the Association present, opportunity has certainly not been wanting in which to develop their ability. Think, for instance, of what a magnificent subject for discussion was offered by Prof. Hartshorne, of Pennsylvania, in a paper on the relation between organic vigor and sex, in which he espoused the theory that the births of females were an indication of excess of formative force, and of males of a deficiency, on the part of the parents; and that female offspring was an index of the highest vigor. He began by alluding to certain papers which Prof. Meehan, a botanist of celebrity, had submitted to the Association, wherein it was set forth that the highest types of vegetation among the larch and coniferous trees were of the female kind. He specifies that the larch, while in its highest luxuriance, and during many years, produces only female flowers; but in its decline it at length produces male flowers, and it shortly afterward dies. Prof. Hartshorne extended this theory to animal life, and undertook to show that, whenever or wherever there was excess of formative power, its tendency was to the production of female offspring. He illustrated his belief by the development of bees, the birth of the queen-bee being the highest, of the drone the lowest result, and preceded by respectively high and low circumstances of nutrition. Sometimes a working-bee—which, being an imperfect female, is of course incapable of impregnation—will give birth to parthenogenetic offspring. Such offspring is always male. The eggs of the queen-bee that hatch males have not been fertilized; and, should she never have been impregnated and lay eggs, they will hatch only drones. In respect to the aphides (plant lice), it is noticeable that, while their food is sufficient and of nutritious quality, their offspring is exclusively females, propagated parthenogenetically; but soon after the supply of food, owing to a change of season or circumstances, is diminished, young male aphides appear. Among the higher order of animals Prof. Hartshorne found an argument in the sex of double monsters. Stating that the birth of double monsters was due to fissure of the ovum and excess of formative power, he asserted that it is well known that in the majority of instances these monsters were of the female sex. He brought forward the vital statistics of different nations and their varying proportion of male and female births in support of his position, attributing the differences to increasing or diminishing vitality; and even the continually lessening reproductive powers of American women formed one of the illustrations of this theory.

SYMPATHETIC VIBRATIONS.

Prof. Joseph Lovering, of Cambridge, Mass., gave an interesting address on vibration, illustrated by an experiment. It was presumed that the members were more or less familiar with Milde's experiment with a tuning-fork and vibrating thread. This optical method of Milde is very much improved by using a large bar of iron and perpetuating the motion by means of magnetic excitement, the vibration being thus maintained for any length of time. A cord 20 or 30 feet in length is thus thrown into vibration. When the first suspension bridge was building in England, a fiddler offered to fiddle it away. Striking one note after another, he eventually hit its vibrating note, or fundamental tone, and threw it into such extraordinary vibrations that the bridge-builders had to beg him to desist. Only recently a bridge went down under the tread of infantry in France who had not broken step, and 300 were drowned. An experiment is often referred to of a tumbler or a small glass vessel being broken by the frequent repetition of some particular note by the human voice. It is said, and may be true, that certain German tavern keepers increase their custom by the occasional performance of this feat. In the Talmud there is a curious question raised as to what would be the damages if a domestic vessel were broken by a noise made by an animal, such as a barking dog. Prof. Lovering here exhibited two pieces of clock-work, each giving a button a circular velocity of rotation. These are to turn a cord much as a skipping-rope is turned. The rotation twists an ordinary cord—or untwists it, as the case may be—and to avoid this twisting a tape is substituted, and a twisting or rotating machine is placed at each end. The chief difficulty now remaining is to have the machines twist in unison, which is difficult, as the two pieces of clock-work vary from each other, but on the whole the experiment is usually satisfactory. The tape was stretched across the stage, and the machines to rotate it were placed at each end. If the string is too slack for one segment of vibration, it subsides into parts, each having a vibration similar to the other. The tighter the string is drawn, the fewer the segments of harmonic vibration. The string started with five waves or segments of vibration. Drawn tighter, these were reduced to four, three, and finally two segments, the nodal point in each instance between the waves remaining perfectly unmoved. With a shorter string the first harmonic note was reached, and ultimately the fundamental note or a single vibration was exhibited. Very high harmonies were shown by means of a very flexible string with a high velocity dividing the revolving tape into very numerous equal segments of vibration, or, as the professor preferred to call them, harmonics.

Petroleum In Santo Domingo.—In a note to the Mechanics' Magazine, Mr. William M. Gabb describes a petroleum-spring situated three miles north of the town of Azua, in Santo Domingo. It is near a stream, the name of which signifies "stinking water." The spring makes its appearance as a stagnant, torpid pool, exuding slowly through a heavy gravel-deposit. A very small area in the vicinity is covered with deposits of pitch, and, for half a mile down the dry bed of a rain-water stream, the gravel and sand are more or less cemented by an impure pitch, sometimes plastic, oftener hardened to asphaltum. The water is colored a dirty brown by the presence of the oil. Jets of gas bubble up at different points near the spring. The gas is not inflammable, and has more of a fetid than kerosene odor. In appearance and mode of occurrence the spring strikingly resembles those of Trinidad and California. It is the only spot on the island where bituminous products are found.

Photographing the Eye and Ear.—Dr. Vogel writes to the Philadelphia Photographer as follows: "That the interior of the human eye has been photographed is well known. The experiment is a somewhat cruel one for a living subject; still there are victims who stand it. I know, for instance, a very handsome young lady, whose brother is a physician, who patiently takes extract of belladonna until the pupil has become sufficiently enlarged; the interior of the eye is then illuminated with magnesium-light, and photographed. In a similar manner has the ear been photographed, that is to say, the tympanum only. A tube is inserted, in which is a mirror inclined at a certain angle. The mirror throws light into the interior of the ear. The mirror is also provided with a central hole through which the illuminated tympanum can be inspected. A system of lenses projects an image on the sensitive plate, and the picture is made in the ordinary manner."

Chemical Influence of Light.—In a recent lecture on the chemical action of light, Prof. Roscoe gives some interesting facts concerning the chemical effects of sunlight at different times of the day, and in different atmospheres. The number of chemically-active rays vary throughout the day. Their maximum is always highest at noon. The curve of the heating rays reaches its highest point after noon, but this is not the case with the chemically-active rays. The chemical intensity appears to depend solely on the height of the sun in the heavens, and at the same distance from noon; on either side it appears to be equal. The chemical power of sunlight also varies with the place. Prof. Roscoe gives the results of measurements at Kew, Lisbon, and Para. At Kew the intensity was 94.5, at Lisbon 110, and at Para 313. An opalescent atmosphere appears to cause the absorption of a large number of the chemically-active rays. Hence the important advantage, in point of vegetation, which those countries have where the atmosphere is clear.

The Leaf a Vicarious Organ.—Some interesting experiments have lately been conducted by M. Calliet, to determine the precise action of plant-leaves in the absorption of water in the liquid form. They have led him to the conclusion that leaves do not absorb water while the roots are supplied. But when the ground is too dry for the roots to obtain it, if water be put in contact with the leaves, they will absorb it for the nourishment of the plant. The experimenter thus educes the fact that the action of the leaf is a vicarious and not a natural function.

Carbolic Acid from Plants.—M. Broughton, government chemist, attached to the cinchona-plantations of Ootacamund, in India, has obtained carbolic acid from the Andromeda Leschmantii, a plant which grows there abundantly. The product is less deliquescent than that obtained from coal-tar, and, owing to the expense attending its preparation, is not likely to compete with the article at present in the market.