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ASCENDING VENTILATING SHAFT.

space, up which the air is constantly passing from the out- parts of bedroom floors, nothing can be said that is unside into the house. At all times the air is finding its way, favorable, granting always that it is laid down with skill and, as the current is directed in an upward course, draught and care. As a rule it should be closely fitted to the floor, is not felt even when the air blows in freely. At the same time and well glued an, nailed down at the edges, so that it can the sashes can be opened or closed, as may be desired, with not become a coating for a thick layer of dust beneath it. out altering the arrangement for ventilation.

Fixed firmly in its place in such a way as to form part of I have recommended and employed Dr. Bird's costless the floor itself, oilcloth can be cleaned with as much facility ventilation so many years with such excellent practical re as can a boarded floor, and can be waxed as perfectly. It sults, I hardly like to venture on a shade of suggestion for does not retain dust; it shows the presence of dust and dirt, its modification. There is, however, one change in it which, and it is a good non-conductor of heat. The substance called while it adheres entirely to the principle, is, I venture to linoleum is, in some particulars, an improvement on oilthink, an improvement in detail. This consists simply in cloth, because it is a better non-conductor. Kamptulicon is letting the lower sash remain unchanged, and in bringing more enduring than either, but it does not admit of such down the upper sash three inches, so as to let it by that dis- perfect cleaning; it catches the dust more, and it never tance overlap the lower. The space above on the upper part looks so bright and cheery as the others do. We are told of the top sash has then to be filled up, and I recommend that it is so much more serviceable, and that is true; but for this purpose a permanent bar of wood, against which then it is not good to have forever in view a structure that the upper sash can close. The advantages of this detail is unchangeable and practically indestructible. An occaare, that the window looks better; that light at the lower sional change of structure is a positive relief, and when it part is saved; that lower blinds are not interfered with; can be obtained at slight cost is a useful luxury. that the interposed piece of wood is out of the reach of the The walls of the landing, like those of the bedroom, servants, so that it cannot be taken away without great should be covered with a paint or paper that will readily trouble; and, that if there be a draught at the space admit of being washed. Failing this, they should be diswhere the sash touches the interposed portion of wood, it is tempered. at the top instead of the bottom sash, and is not felt by those who are passing the window on ascending the stairs.

It is always good practice wherever it is practicable to The costless ventilation once effected, it should be in

make an opening from the stair-landing into, and out of, operation all the year round. It is true that in cold weather

i he roof of the house, or into the stack of the chimney. If it causes a lower temperature on the landing than would

the landing be just under the roof, then it is good to get a exist if the window were absolutely closed; but this must

direct opening through the roof, or the cock-loft leading to be met by increasing the warmth within the house, not by it, so that there may be an immediate communication with the process of excluding the outer air.

the outer air above. In most houses this upper landing. It will be soon detected in windows in which the costless

place is connected by the staircase with the whole of the ventilation is set up, how large a quantity of dust there is

lower part of the house. The house from below ventilates in the air which finds its way into the dwelling-house of the

into it, and if upon it there be no efficient outlet, it is in a great city. The space through which the air passes is very

bad position indeed. Should there be an intervening floor quickly charged with dust, some of which settles on the

between the floor and the roof of the house, a small shaft panes of the window and the framework, and requires re

should be carried up, and beneath that shatt a gas-burner moval at short regular intervals. It is raised by some as an

inay with much advantage be suspended, so as to make the objection to the system of costless ventilation that the dust -haft a chimney for the conveyance of the products of the enters so freely through the permanent opening as to be

gas and of air, away from the interior of the house.

THE WATER-CLOSET ON THE STAIRCASE LANDING. come, in its turn, a nuisance. Hence, we often find the opening partly filled up with a sandbag, or else with a plate

In the houses of crowded cities the worst sanitary diffiof perforated zinc, the openings of which are quite closed culty of all lies in the arrangement of the water-closet on up with dust. Both these practices are bad; the open space

the landings of the staircases. Some sanitarians propose to should never be closed. In spite of the acknowledged in

meet these difficulties by introducing the dry earth-closet convenience of dust, it is far better to have a free admission system, or by some other special system distinct from what of air than to exclude the air. In practice, moreover, the

is in general use. I do not object to such suggestions where dust nuisance is less than would be expected. It is only they are practicable.

[TO BE CONTINUED.) occasionally present, while bad air, if outer air be kept out, is always present.

RURAL MANNERS. The floor of the landing should be treated precisely in the same manner as the floor of the bedroom. In the course of

POLITENESS. the tread in the centre of the landing, for a width, say, of The first and most obvious reflections which arise in a from eighteen inches to two feet, a line of carpet may be man who changes the city for the country, are upon the laid down, but the floor space on either side of the carpet different manners of the people whom he meets with in those should be uncovered, and if it be of wood it should be two different scenes of life. By manners I do not mean dry scrubbed and treated with wax and turpentine, when morals, but behavior and good breeding, as they show themthe boards will allow of it. Where the staircase and land selves in the town and in the country. ing are of stone, nothing is more healthful than the stone And here, in the first place, I must observe a very great itself duly cleaned and whitened. When the floor surface revolution that has happened in this article of good breedis of indifferent wood or stone, it may, with advantage, being. Several obliging deferences, condescensions, and subcovered with oilcloth, with the center carpet. In no case missions, with many outward forms and ceremonies that should the whole of a landing be carpet-covered so as to accompany them, were first of all brought up among the make the carpet hug the wall. A floor covered in that man voliter part of mankind, who lived in courts and cities, and ner holds the dust, and keeps the air charged with dust, listinguished themselves from the rustic part of the species every step and every gust of air that moves the carpet from (who on all occasions acted bluntly and naturally) by such beneath tending to waft some particles of dust into the air a mutual complaisance and intercourse of civilities. These above.

forms of conversation by degrees multiplied, and grew Of oilcloth as a covering for landings, passages, and outer troublesome; the modish world found too great a constraint

in them, and have therefore thrown most of them aside. A NIGHT WITH A COMET.* Conversation, like the Romish religion, was so encumbered with show and ceremony, that it stood in need of a refor On Thursday morning, June 23d, an employe of the mation to retrench its superfluities, and restore its natural Courier-Journal, of Louisville, was on his way to the office good sense and beauty. At present, therefore, an uncon at the early hour of half-past three. Casting a look northstrained carriage, and a certain openness of behavior, are ward he saw a comet in the sky not far from a very bright the height of good breeding. The fashionable world is star. That star was Capella, the most brilliant member of grown free and easy; our manners sit more loose upon us: the constellation of Auriga, and the comet was the now nothing is so modish* as an agreeable negligence. In a famous No. 2 of 1881. A neighbor of mine in Richmond word, good breeding shows itself most, where to an ordinary saw it at about the same time. The first news that I reeye it appears the least.

ceived of the presence of this unexpected celestial guest, If after this we look on the people of mode in the country, came through the Codrier-Journal of Friday, June 24th, we find in them the manners of the last age. They have no and at 1:30 a. m. on Saturday, June 25th, I was busy getting sooner fetched themselves up to the fashion of a polite out the University telescope for an observation. This inworld, but the town has dropped them, and are nearer to strument was made to our order by Alvan Clark & Sons, the first state of nature, than to those refinements which for the noted telescope-makers of Cambridgeport, Mass. It has merly reigned in the court, and still prevail in the country. in aperture of six inches, a focal length of eight feet, magOne may now know a man that never conversed in the nifying power (as stated by Alvan Clark & Sons) from world by his excess of good breeding. A polite country hirty-six to six hundred diameters, and is equatorially squire shall make you as many bows in half an hour, as mounted on the largest tripod ever sent from the manufacwould serve a courtier for a week. There is infinitely more pory. Its power of definition may be estimated from the to do about place and precedency in a meeting of justices' fact that it separates double stars whose centers are distant wives, than in an assembly of duchesses.

only one and one-half seconds. This rural politeness is very troublesome to a man of my While mounting this elegant instrument it was altogether temper, who generally takes the chair that is next me, and natural to take a survey of the sky. Every part of the firwalk first or last, in the front or in the rear, as chance di mament has its own special glory, and one of the most rects. I have known my friend Sir Koger's dinner almost glorious portions of it is found in the milky way running cold before the company could adjust the ceremonial, and up through Perseus and Cassiopeia to Cygnus, near the be prevailed upon to sit down; and have heartily pitied my zenith, and thence to the southern horizon by way of Sagitold friend, when I have seen him forced to pick and cull his tarius. Quite near this belt we see the lovely Vega in the guests, as they sat at the several parts of his table, that he Lyre, and Altair in the Eagle, two of the fairest gems of the might drink their healths according to their respective northern celestial hemisphere. Then in Perseus and Sagitranks and qualities. Honest Will. Wimble, who I should tarius these are nebulæ, which, by the magic of the telehave thought had been altogether uninfected with ceremony, scope start up into gorgeous cohorts with glittering helmets gives me abundance of trouble in this particular. Though

and spears.

The nebular hypothesis imagines that the he has been fishing all the morning, he will not help him clouds of star-dust of millions of years ago were slowly self at dinner till I am served. When we are going out of fashioned into suns, planets and satellites. But the telethe hall, he runs behind me; and last night, as we were scopic enchantress waves her wand over this long interval walking in the fields, stopped short at a stile till I came up of ages, and the vapor so dim and vague to the naked eye to it, and upon my making signs to him to get over, told of to-day flashes into a universe of worlds. When I first me, with a serious smile, that sure I believed they had no turned our instrument on one of Messier's nebulæ in Sagitmanners in the country.

tarius, I was startled into an outcry; for a sudden wonder There has happened another revolution in the point of and joy smote upon my heart, as though God himself had good breeding, which relates to the conversation among men

spoken to me. of mode, and which I can not but look upon as very extraor There is something unique in a night scene beheld by a dinary. It was certainly one of the first distinctions of a solitary observer. If you are like the witty Frenchman, who well-bred man, to express everything that had the most re said, “Yes, solitude is sweet; but how much sweeter to have mote appearance of being obscene in modest terms and dis some one by you to whom you can say, how sweet is solitant phrases; whilst the clown, who had no such delicacy tude!"—if this be your temperament, I could hardly advise of conception and expression, clothed his ideas in those you to rise from balmy slumber at 1:30 a. m. to gaze at the plain homely terms that are the most obvious and natural. heavens. But if there be in your spirit a touch of the mysThis kind of good manners was, perhaps, carried to an ex

ticism of Hannah, in "Adam Bede;" if you at all resemble cess, so as to make conversation too stiff, formal, and precise; that gentle enthusiast who so loved to be alone with God, for which reason (as hypocrisy in one age is generally suc

then you may find that to be alone with God's heavens is ceeded by atheism in another) conversation is in a great not a solitude, but a communion. measure relapsed into the first extreme; so that at present

GROWTH OF A COMET. several of our men of the town, and particularly those who have been polished in France, make use of the most coarse,

You see there on the blackboard an egg which I have uncivilized words in our language, and utter themselves of drawn. Just here is a bright point. Can those of you who ten in such a manner ay a clown would blush to hear.

are on the outskirts of the audience see it. Raise your This infamous piece of good breeding, which reigns among the coxcombs of the town, has not yet made its way into the

hands. (Half a dozen hands went up.) Very well. That country; and as it is impossible for such an irrational way of point represents the germ or nuclens, where life begins. conversation to last long among a people that makes any Agassiz and others have described the very interesting proprofession of religion, or show of modesty, if the country

cess of its development. gentlemen get into it, they will certainly be left in the lurch. Their good breeding will come too late to them, and they

This is intended for such an egg as the little boys and will be thought a parcel of lewd clowns, while they fancy girls find under the barn floors or up in hay lofts. Rethemselves talking together like men of wit and pleasure. member, however, the old adage: "Omne vivum abovo"(End of Required Reading for January.)

every living thing comes from an egg. * The vulgar use of this term has, I suppose, disgraced it. It would * A lecture delivered in the Hall of Philosophy at Chautauqua, pot now be endured in polite con :ersation, much less in polite writ August 16, 1881, by Prof. L. G. Barb ,ur, Professor of Mathematics ing.

and Astronomy, Central University, Richmond, Kentucky.

DECLINE AND FALL.

Here I show you another egg, shaped much like the for But there seems to be about as good reason for supposing a mer, but not so solid looking. Older boys, and girls, too, as repulsive force also in the sun. Or, if I might suggest, there Miss Herschel and Miss Mitchell, find them in the sky. is a mutual repulsion between the sun and the matter of This is the way a comet looks when it is first seen in the which the tails of comets are composed. far blue depths of heaven. And you see here also a germ.

RAPID FORMATION OF THE TAILS. I do not say that all comets have germs. Perhaps some do not; at least in some no germ is detected, and such never

"The tail of this comet (Donati's, 1858) increased in length come to much. I have chosen one with a germ. But what

at the rate of two millions uf miles per day; that of the great is it doing now? (The lecturer here began to develop the

comet of 1811, at the rate of nine millions of miles per day; comet on the blackboard.) The comet and its germ seem to

while that of the great comet of 1843, soon after passing be expanding. Yet that may be owing to the fact that they perihelion, increased at the rate of thirty-five millions of are coming nearer to us.

miles per day."' * You may well imagine that the tails of But see again! A line of light leaps forth toward the sun.

some comets grow rather long. So they do. The comet of You will please understand that the sun is up yonder above

1843 had a tail two hundred millions of miles long; enough the blackboard. Now another line nearly parallel on the

to reach entirely across the orbit of the earth and lap over left, and another here on the right, with a sound like "choo!

it some millions of miles. If a railroad train had started choo! choo!" as we imitate to our little children the start

from the head of this comet to traverse the whole length of ing out of a train on the railroad. Now the intermediate

the tail at the speed of sixty miles per hour, day and night, space is filling up, and you see a very respectable white fan, Sundays included, the journey would have required three just such a one as I saw carried by the comet of last June.

hundred and eighty years. The comets had fans long before the ladies used them. Our

Comets have had more than one tail. One had as many comet here perhaps needs one, as it is approaching the sun,

as seven, all trending in different directions. These facts and getting very warm.

indicate that comets contain diverse kinds of matter, the See, now, streaming out on each side something like hair.

tails being formed successively, and at different degrees of It turns back in the general direction opposite to the sun.

temperature. It reminds one of a little girl at play with her brothers: she runs so fast and gets so warm, and then with both hands The nucleus of a comet usually seems to diminish as it brushes back the hair from her forehead.

approaches very near the sun. One would have thought it The Greek word for comet (kometes) was originally an would increase by the expansive power of heat; but the adjective, meaning hairy. Thus Aristotle, in his meteor- contrary is the observed fact. Look at the planet Jupiter, ology speaks of a hairy meteor. By a natural transition, whose solid or possibly liquid body is surrounded by a dense the adjective has become a substantive; the termination has cloud. If that cloud should be heated sufficiently, it would been lopped off, as we forever do with classical words; and become transparent, and the body of the planet could be hence we get our English designation for a comet.

seen through it, so that Jupiter would appear smaller than The process of formation still goes on. The hair streams it does at present. If the cloudy matter should cool down back, and thus the tail is pr uced. I extend it to the bottom of again and become opaque, the planet would seem to grow the board; but I cannot very well finish the job, as the tails larger. Thus the coma of a comet diminishes, but the are millions of miles long, and I have neither blackboard nucleus apparently increases in size when it first goes away room nor time sufficient for the completion.

from the sun. The tail, meanwhile, lessens, like a man You observe a dark undefined strip down the middle of who has passed the hot noon of life, and has less hair on his the tail. This is due to the fact that the tail is hollow. | head, but more head and brains. Back, back, the poor Out toward the edges you look through a larger mass of the comet goes, until it resumes its primeval state. Brave luminous matter, consequently the edges appear brighter chanticleer becomes an egg again. This might be called an than the middle. Something similar is seen when we ex

instance of “reversion." amine a hair with a microscope. A hair is tubular, and

AN EXCEPTION. down the middle of it you see a light colored stripe, reversing the colors of the comet's tail, but evidently caused in

This is the ordinary and periodic career of a comet; but the same general way.

there is a remarkable exception in the case of the one named The tail of the comet is not straight, but bends gracefully

after the Austrian captain, Biela. This comet was journeyback like a superb ostrich plume. This alone overthrows ing along around the sun, all right, as innocent as Adam in the old theory that the dark central line was the shadow of

the garden of Eden, and as lonely. "Man the hermit the nucleus.

sighed till woman smiled," after which he sighed far worse You may be curious to know why the matter surrounding

than he did before. Well, Eve was taken out of his side; the nucleus thus streams out away from the sun. An old,

and a fainter comet was made out of Biela's. Lo! there but long ago abandoned theory was that it rose up as

were two of them, companion comets, traveling the journey smoke and vapors rise from the earth; toward the sun be of space together. The Adam comet was the brighter and ing down, and away from the sun, up. This hardly merits

the Eve comet the dimmer, just as it ought to be. But a serious refutation. Neither can the tail be like the smoke

soon the Eve comet began to brighten, and kept on gettrailing cut behind a locomotive; for that has an alignment ting brighter, until it outshone the Adam comet-just as nearly parallel with the course of the locomotive itself,

it ought not to be! As you may well suppose trouble came while the direction of a comet's tail is always nearly op

of all this, but I can not stop to tell the rest of the story. posite to that of the sun.

The ac repted conjecture now is that the sun has a repulsive force as well as a force of attraction, and the repulsion

Amaryllis, at the age of twenty, had a fine suit of hair,

four feet long. Amaryllis is now forty-five, and her hair is acts with prodigious power on at least a part of the cometic matter. We do not know why the sun attracts the planets only three feet long. Yet it has been growing all the while and the comets. We only account for the planetary and

at the rate of four to six inches per year. It ought to be one

hundred or one hundred and fifty inches longer at the age of cometary motions by the supposed power of universal gravitation. Since Newton overthrew the vortices of Des Cartes, forty-five than at the age of twenty. Where are the chestthe scientific world has received the theory of attraction. * Loomis.

WHAT BECOMES OF THE TAILS.

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PATHS OF THE COMETS.

“ The sun

nut, auburn, or raven locks that adorned her twenty-five dom we meet with a wonderful variety of curves, but the years ago ? Answer that, and perhaps I may be able to tell straight line does not disappear. May I say that since it you whither the tails of the comets go.

measures the shortest distance from one point to another, it You will at once see, however, that the matter of the tail offers an economy of which even the august. Creator avails lessens every time the comet whips around the sun. The himself. Here is a leaning, swaying plant; curves abound sun, like a cruel boy, hatchet in hand, cuts off their tails in it, but you see two straight lines in that opening bud. not by inches, but by millions of miles. When they grow A German teacher once said to me, “ The first thing is to out again, he cuts them off again, remorselessly; and so on, have a good master; and who is the best master, if not toties quoties. After a long, long time, all the cometic tad | God?” I accept the suggestion, and go to the fountain head poles will turn into frogs-another fact for Mr. Darwin, of art. whereby to prove that tadpoles have been evolved from Here is an enlarged copy of a leaf by the Great Master: a eomets.

beech leaf which I picked up the other day here at Chautau

qua. What do we see? A curved periphery, or bounding In what sort of orbits do they move? Do all or most of line, and that again used as a foundation for a frill, scollop, them return to the neighborhood of our sun? These ques

serration, or whatever you may please to call it. But, also, tions and their answers are more closely related than might

we see a straight axis running down the centre, and a score appear at first. Understand in the outset that none of the

of straight lines branching off right and left in parallels. In heavenly bodies wander about, even though Byron did

the next drawing you see a fuchsia, taken from a specimen dream of earth's "wandering darkly through eternal space.

in a rustic flower box in front of Brother Lewis Miller's cotDo you remember that grand saying of Gothe, in the Angel

tage. In the pistils and stamens the straight line appears. Song, prelude to Faust:

In this outline of a maple leaf, copied from nature, the

straight line almost disappears, but not quite. Bounds his predestined course along.''

Now for the animal kingdom. The straight line is hardly All the orbits are exhibitions of inexorable law, and yet of

seen at all. These are two shells copied from specimens on

sale at the stand near the Point. The Great Artist has lavmost graceful motion. You have doubtless noticed the stern self-repression by which I have been restraining my steps

ished an infinite variety of curves even on the mollusks, from the flowing fields of mathematics. That ancient and

and the vertebrates of land and water abound in elegant honorable science measures a yard of tape, or the orbit of a

forms. These curves are of very high order, geometrically eomet; weighs an eighth of a grain of morphine, or suns and

considered; yet while we are sure that they ail have their systems. It is not, indeed, studied at Chautauqua, where

equations, those equations are not known. This is a departlanguages, ancient and modern, Semitic and Indo-Eu

ment into which some coming mathematician may enter. ropean, are investigated with such avidity. But this is be

It is a virgin soil. I take special interest in the thought cause all good Chautauquans are supposed to have mastered

that man's spiritual life manifests itself by the help of curves. mathematics before coming hither. You are not, then, like

They are its language, and therewith we smile, we bless, we the excellent old lady out in Kentucky, who was very ill,

worship; we give outward expression to our hope, our trust, and, in fact, was thought to be near her end. As she lay one

our love. This is visible in the works of all the great artists; day with her eyes closed, and apparently asleep, some

perhaps most of all in Raphael. It has been said that friends sitting by began to discourse of the future state. The

Raphael himself could not draw a straight line; perhaps not thought was advanced that the subjects of our liveliest in

without a straight-edge. Examine the photograph of his terest here would engage our chief attention there; as, for

Sistine Madonna, in Newton Hall. I have found, amid an instance, mathematics. “Mathematics!” said the invalid, opulence of curves, a half dozen straight lines obscurely inopening her eyes, " if I have to study mathematics there, I

troduced on one side of the picture. Probably they are don't want to go!" And she actually got well! (Laughter).

meant to give us the true up and down of the picture, withBut I am not addressing a half-dead audience; and so, trav

out attracting attention to themselves. In Titian's “Aseling along the dusty pathways of fact, fancy and fun, let us

sumption of the Virgin," and Murillo's “Immaculate Con

That take a peep through the hedge into the violet-sprinkled ception,” scarcely a vestige of a straight line is seen. mead of geometry. When most people hear of geometry,

is, seen on the surface. You must look below the surface if they either stop their ears, or run away, or else begin to

you would behold them; you must look back into the artthink painfully of an array of stiff, formal figures-of unin

ist's mind. When the sign painter, or ornamental type cutviting angles, and squares, and crooked things generally.

ter, gives us a very elaborate letter, with ever so many flourBut a curve is as geometrical as a straight line; I may say

ishes to it, the trained observer requires that underneath all more so, for it is geometry on a higher key. There is no

there shall lie the simple, severe lines, curved or straight, graceful line in existence that does not have its equation.

which would make a good plain letter. Then, also, a young In the structure of this wondersul universe, the All-wise

artist friend of mine said to me lately: “ In drawing the Architect has used a great variety of lines, and you will find

mouth, we have a straight line in our mind; so with the a fruitful theme of thought in the inquiry, What use does eyes." "Just so," I replied, “and God, the chief artist, had he make of them?

the straight line in his mind when he made our features.

We have in our mind what he first had in his; we interTHE STRAIGHT LINE.

pret his thoughts." Ruskin says somewhere: “The fact is, the world is round,

WHERE THE COMET ORBITS COME IN. and all that is in it; except the works of man, and they are Between the straight line whose equation is of the first often very flat.” Hogarth finds curves in clouds and hill- degree, and the curves mostly employed by nature, which tops; everywhere, except in crystals. Let us, however, use are of the third and higher degrees, we find the curves of our own eyes a little; and here (exhibiting a large charcoal the second degree, in one or other of which the planets, the sketch) are two of the crystals, those flowers of the mineral satellites and the comets move. There are just four of kingdom. This is calcspar, and that quartz crystal. Basalt these—the circle and the ellipse, which are re-entrant may perhaps be classed among the crystals; and the layers curves, and form closed figures; and the parabola and the of coal, limestones, and sandstones, may fairly be said to hyperbola, whose branches diverge forever. It was reserved present flat surfaces.

for the genius of Sir Isaac Newton to demonstrate that they Let us enter the domain of life. In the vegetable king-flow from the one universal law of gravitation.

C

The Almighty might have selected some other law of at- | Some misguided individuals would rather think of you than traction by which the orbits would have been far more of the ellipse. complicated. In fact, the old Greek astronomers thought So the planets whispered to our race; how patiently, too, they were so. They invented cycles and epicycles in bewild through the long centuries, dering confusion. But one trait of the All-wise Intelligence

“From the sky serene and far, is a disposition to effect his ends by the simplest means pos

Their voice fell like a falling star," sible.

until at last a God-fearing German gazed steadfastly into the Mankind have only at last, after fifty-five centuries, come heavens and said, “I see!" Yet again the comets said, to understand the mechanism of the heavens. If the laws

“Look at us; do not be afraid; we will not hurt you. We of orbital motion had been much more intricate, man

will move slowly, quietly through the sky, tracing our must have been built on a larger intellectual scale, or else ellipses through space.' And a God-fearing Englishman have been forever confounded by the celestial maze. Sup

saw at last, and now he who wills may see. pose the equations had been of the fifth or tenth degree, in

PARABOLAS. stead of the second! Again, one undying attraction of the Pythagorean system, revived by Copernicus, and now trium

Bear in mind that only four curves are possible to comets phant in christendom over the Ptolemaic, is this very sim

under our present law of gravitation; that two of these, the plicity. We are made in the image of God. The skies un

circle and the ellipse, are closed curves; that no circular orroll their illuminated missal before us, as the mother of Al

bit has ever been discovered, but many elliptical ones; and fred the Great did to her children. The text is not too dif

that any true and independent American citizen who has ficult for strenuous endeavor to decipher; we persevere, and

no flowers to wave in the wind, but who has a silver dollar the volume is ours.

in bis pocket, may, by turning that dollar slowly over, see ART AND SCIENCE

before him in succession the orbits of all the planets, all the I do not know how it will strike you, but to my own mind

satellites, and very many of the comets.

Now for the two curves that are closed at one end and one of the most interesting features of this whole subject is

widen out forever in their two branches. All good Chautauthe explanation of the fact that art has so outstripped sci

quans are familiar with parabolas. Some of you have made ence in the realm of form. The curves of planetary and

hundreds, and even thousands of them. I will describe one cometary motion, while shapely enough, are specially com

for you with a piere of chalk. Look sharp! Here goes! mendable for simplicity and utility. It is mainly in the higher curves that grace and beauty shine forth. In the [Tossing a bit of chalk in the air.) Except the deviation

caused by passing through the atmosphere, that may be study of these man has copied, not originated. • Leonardo da Vinci advises the artist to be forever observing and for

considered a very respectable parabola. Our base ball play

ers make countless such curves. Their" bee-lines" are parever copying. The lines were too high for us to invent.

abolas with large parameters, and their “flies” are ditto Happy is he who can detect them, understand them, love them, and make them his own. They are ours when we

with small parameters. When an astronomer has found a

comet in the sky, the first thing is to see if he can "catch it can reproduce them at will, and employ them fittingly.

on the fly,” or, in more scientitic language, fit a parabolic But remember, they are God-given; if they had not been

curve to its observed path. At least three good observations given, high art would have been impossible.

are necessary. The simpler lines our Maker has left us to work out for ourselves, and it is certainly remarkable that the four curves

For most purposes a parabolic orbit fits well enough in

many instances. But while we may not be able just yet to mentioned were discovered by the ancient Greeks before the Christian era. The history of human thought scarcely af

get a better fit, be it said that in all likelihood, as there is

no circular orbit known, so there is no parabolic orbit, fords a parallel instance of the ardent study of apparent ab

strictly speaking, in all the solar system. stractions which afterwards were found to be embodied in most concrete realities. A few singular curves, kept as a

"THE RIGOR OF THE GAME." precious thought-treasure by Greek and Saracen, and trans “A bright fire, a clean hearth,” said Sarah Battle, the mitted to the Christians. Why? Because it is seen at last champion whist player, “and the rigor of the game!" that they were the principles of the handicraft of him who Bad life-occupation; good apothegm. Bad thing to do; built the universe. He has made us so that what interests good thing to say—at least in the exact sciences, where you him shall also interest us.

ought to be exact, one would think. The æsthetic element in our nature is like the bird that All the text-books in mechanics say that the curve deflies upon easy pinion over mountain height; the mathe- scribed in the air by the piece of chalk I tossed up a moment matical like the locomotive that climbs slowly up their since, is a parabola. Every year I prove it to my classes in sides. The former learns directly from the Great Teacher; relation to projectiles. But in utmost rigor it is not true. the latter creates for itself. In the former the Heavenly It would be true if the center of the earth were at an infinite Teacher gives us theorems to believe; in the latter, problems distance beneath us; or still more precisely, if a plumb-line to solve, and withal, hints for their solution.

here were accurately parallel to a plumb-line yonder. In fact, this parallelism is assumed in the demonstrations of the

books. But since the plumb-lines converge, the curve was An infinitely curious subject is that of nature's hints. after all a very elongated ellipse,-such as you see in the Nature whispers to us. See this drawing in which the dollar just before the ellipse turns into a straight line. whisper comes to us through the lips of a flower. First it A sufficient reason why there are no circular orbits is that tells us of the circle hidden in its corolla. But this is not at a given point of its path the velocity of a revolving body the whole of its lesson.

would have to be exactly so much, and not the least bit If I had the preternatural hand-cunning of a Frank Beard, more or less. A trifle more or less would throw it into an I would sketch in a sweet little girl here. A thousand ring- ellipse. For instance the attraction of Venus or Mars would lets should fall adown her shoulders; a thousand graceful puil the earth out of a circular orbit; and once out, it could .curves cling about her; and the flower—if that might be never get back. should wave in the wind and say, “Do you see my ellipse, Thus, too, exactly so great a velocity, neither more nor less, little maid? See, see, here it is, here it is!"

at a given point, would make a comet move in a parabolic But hold, pretty one; you are distracting my audience. orbit; but the disturbing attraction of any third body would

HINTS.

ܙܙ

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