CHAPTER X.

_Marbles.--Antiquity of the game.--Method of manufacturing

them.--Ring-taw.--Mr. Seymour, the Vicar, and Tom, enter the

lists. The defeat of the two former combatants; the triumph of

the latter.--A philosophical explanation of the several

movements.--The subject of Reflected Motion illustrated.--The

Vicar’s apology, of which many grave personages will approve._

In our last chapter we left Mr. Seymour and his reverend friend on

their way to Ivy Cottage; it is only necessary to state that the major

received them with that satisfaction and gratitude which the nature of

their visit could not fail to produce. Plans were proposed, and

arrangements concluded for the furtherance of the object we have

announced; in short, in the brief space of an hour, the major had

determined the course of his future life, and had framed schemes of

happiness, and visions of domestic peace, which he impatiently sought

to realize. The vicar was detained by the major, but Mr. Seymour

quitted Ivy Lodge and returned to his family. He found the children

engaged in playing at marbles. Tom was displaying to his sisters many

instances of his adroitness and skill in shooting at and hitting

marbles.

“Why, Tom!” exclaimed Mr. Seymour, “how came you possessed of such a

multitude of marbles?”

“By luck; good luck, papa; I won them all before the holidays; and I

can assure you that my school-fellows acknowledge me as one of the best

players at _ring-taw_ in the school.”

“Justly, then, has your merit been rewarded,” said the father. “Have

you not read of the skilful Roman, who could blow peas through a quill,

and deposit them with such nicety on the point of a pin, placed at some

distance, as rarely to miss his aim?”

“And what was his reward?” asked Tom.

“A bushel of peas, my boy, which the emperor commanded to be presented

to him. But do not misunderstand me, far be it from my wish to

disparage your skill; whatever we undertake, we should endeavour to

accomplish; I am, therefore, well pleased to find that you can play at

marbles with so much success.”

“I wonder who invented marbles?” said Tom.

“That question, my dear, must be addressed to Mr. Twaddleton, who, I

have no doubt, will immediately answer it.”

Scarcely had these words been spoken, when the vicar appeared on the

lawn. Mr. Seymour informed him of the subject of their conversation,

and added, that he had just told the children he was sure he would

readily answer their question.

“Not so readily as you may imagine,” replied the vicar; “but I will

tell you all I know upon the subject. It appears to be a very ancient

game; for it is stated by Suetonius, that Augustus, when a youth, spent

many hours in the day in playing with little Moorish boys ‘_cum

nucibus_,’ that is, _with nuts_, which appear to have been then used in

the very way in which you now play with your marbles. In later times,

round stones, picked out of gravel, were introduced for this purpose.

The marbles which you now hold in your hand are substitutes of still

more modern invention. The best of them are imported from Holland,

where, as I have been informed, they are manufactured by grinding

fragments of alabaster and of other stones, in an iron mill of a

peculiar construction, in which there are several partitions furnished

with rasps, which turn with great velocity, by means of a stream of

water; and thus, having rounded the stones, project them out of

different holes for which their size may adapt them. Thus manufactured,

they are brought down the Rhine, and from thence dispersed throughout

Europe; immense quantities are also exported to India and China. There

are, however, as you well know, inferior kinds, which are of home

manufacture, and consist of potter’s clay covered with a glaze, and

burnt in a furnace.”

“I have often wondered what is the meaning of the words _taw_ and

_ally_,” observed Tom.

“Why, your _taw_ is a brown marble, and your _ally_, if I remember

rightly, a very white one; is it not so?” asked the vicar.

“To be sure,” said Tom.

“Very well, then,” said the vicar, “the words are clearly abbreviations

of _tawny_ and _alabaster_.”

“Now then,” said Mr. Seymour, “for a game; what is it to be, Tom?”

“_Ring-taw_ for ever!” cried Tom; “it is the only game of marbles

worthy of being played.”

“It is really so long since I left school,” observed his father, “that

I must beg you to refresh my memory, and give me some instructions

about this favourite game of yours.”

“I will tell you all about it. We must first draw a circle, on which

each player is to put a certain number of marbles to be previously

agreed upon; we then make a mark at some distance, which is called the

_offing_, and from which we are to shoot at the marbles in the ring.”

“That is all very intelligible,” observed his father; “and I suppose

the object of the player is to shoot a marble out of the ring, which

not only gives him that marble, but entitles him to shoot again at

another, and so on, until he misses, or all the marbles are won.”

“That is right, papa.”

“And a good marksman,” observed the vicar, “who has the first shot, may

easily win the game, before any other player can gain the opportunity

of shooting at a single marble.”

“I see that clearly,” said Mr. Seymour; “he may strike out a marble

from the circle, and then shoot at another, and in this manner traverse

the whole ring; I therefore conclude, that good players will always

demand a large ring, or else there would not be much chance for any

one, except for him who played first.”

“That is the game; but I must tell you,” said Tom, “that if the player

should leave his own marble in the ring, he is at once put out; and

should it be within a certain distance on the outside, an adversary may

shoot at it, and by hitting it, put him also out of the game.”

“I believe that I am now a perfect master of the subject,” said Mr.

Seymour; “what say you, vicar?”

“I understand it; and it appears to me to be capable of some scientific

calculation; but the practical results must, of course, differ very

widely from the theory, for the unevenness of the ground, and the

inaccurate construction of the marble, are circumstances which never

can be duly estimated.”

“Certainly not,” replied Mr. Seymour; “these difficulties even exist at

the game of billiards(25), where the table is smooth and perfectly

horizontal: but we do not require perfect accuracy, an approximation to

it will be sufficient for the purposes of illustration; we will,

therefore, if you please, proceed at once to the game, and I will

endeavour to point out to Tom the nature and direction of the several

forces by which each marble will be influenced.”

Tom, accordingly, like the son of Cornelius Scriblerus, converted his

legs into a pair of compasses, and described, with the toe of his shoe,

the necessary circle upon the ground. Each party, by agreement, placed

two marbles upon the ring, and it fell to the lot of the vicar to open

the campaign. Mr. Twaddleton then advanced, and with the assumed air of

a true knight-errant, approached the ring, exclaiming with a loud

voice, and with a gesture of inexpressible drollery, “I demand gracious

leave that I may be delivered of my vow, and forthwith combat in the

lists;” so saying, he unfurled his red banner, and sounded a trumpet;

or in more humble phraseology, he extracted his hand-kerchief from his

pocket, and applying it to his nasal organs, produced a loud and

thrilling blast, which frightened every sparrow from its resting-place.

After this preliminary ceremonial, he marshalled his limbs into the

most appropriate attitude, and thrusting one hand behind the exuberant

tail of his coat, he, with the other, shot forth his missile at the

largest marble opposite to him. His _taw_ faithfully delivered its

errand, and inflicted such a blow upon the paunch of his antagonist,

that although nearly twice the size of its assailant, like a true

bully, it skulked off, and retreated several feet beyond the lists;

but, alas! the little marble of the vicar, unlucky wight! was so

stunned by the operation, that it staggered, and reeled backwards into

the ring, and thus, according to the established law of the field,

completed by one act the total defeat of its luckless commander.

“Your marble is left in the ring!” exclaimed Tom, with a shout of

triumph.

“I see how it happened,” said Mr. Seymour; “the vicar struck the marble

plump, or ‘played a full ball,’ as we say at billiards, and the result

easily admits of explanation. You already know that a marble possesses

elasticity; when, therefore, the one in the ring was struck, it went

off with a velocity equal to that with which the striking marble

approached it, while the latter, in return, received a blow equal to

that it gave, which destroyed its motion. When we go back into the

library, I will exhibit a very pretty experiment in farther elucidation

of this philosophical truth.”(26)

It was now Mr. Seymour’s turn to enter the lists. He carefully applied

his knuckles to the ground, and taking aim at a little marble which he

had selected as his victim, gallantly shot the missile from his thumb

and finger; but, alas! alas! the goddess, whatever may be her name, who

presides over this species of tournay, doubtless saw the impending fate

of her favourite, and, after the example of Venus, who turned aside the

weapon from Æneas, assumed the shape of a small pebble, and thus

arrested the fatal course of the marble, and gave it a new direction,

which sent it curveting through the ring, without committing one single

act of devastation.

“Bravo! bravo!” exclaimed Tom, “it is now my turn.”

The boy, according to the usage of the field, might at once have won

the game by striking his father’s marble; but he was too magnanimous to

take such an advantage, and too eager to display his own skill, to cut

the game short by a manœuvre: he had determined to win his laurels by

hard fighting and generalship. He accordingly proceeded to strike a

ring marble; in effecting which he had, like the vicar, challenged a

_gigantic knight_ as his antagonist; but, instead of striking it

_plump_, he struck its upper quarter, so that it was rolled out of the

ring, while the striking marble, imparting only a portion of its

momentum, continued to move forward after the impact. This course was

greeted with the acclamations of Mr. Seymour and the vicar, the latter

of whom declared it to have been “nobly run,” and gallantly

accomplished; and extracting a sixpence from his waistcoat pocket,

exclaimed, after the manner of chivalry, “_Largesse, largesse_, glory

to the sons of the brave! glory to the invincible knight of the taw!”

The boy had not only struck the marble out of the ring, but he had, at

the same time, contrived to place his own marble in the most favourable

position for his future operations; and, indeed, it may be here

observed, that in this consists the art of playing the game. It is

almost unnecessary to add that Tom won every marble in succession.

Mr. Seymour then proceeded to explain the laws of impact, by which the

movement of each marble was directed. He observed, that the subject

embraced two propositions, viz. the direction of the _object_ marble

after having been struck, and that of the _striking_ marble after the

stroke. He said that, if a straight line were drawn between the centres

of the striking and object marbles, it would necessarily pass through

their point of contact, and, if continued, would represent the path of

the latter after the blow. In order to find the direction of the

_striking_ marble after the shock, he told him that he must imagine a

tangent to the path of the _object_ ball drawn from its centre, and

then a line parallel to it, from the centre of the striking marble; the

latter of which would be the required path.

Mr. Seymour now inquired whether there was any other game of marbles at

which they could amuse themselves.

“The game which we call ‘_lagging out_,’” replied the boy, “is amusing

enough. It consists in striking your marble against the wall, and

making it rebound, so as to hit any other marble that is placed at a

certain distance from it, or to come within a span of it.”

“I understand,” said his father, “and, like _ring-taw_, it may be made

subservient to our purpose of illustrating the doctrine of forces;

although I think that the principle of _reflected motion_ may be more

readily explained by the rebounding ball.”

Mr. Seymour here took the elastic ball, and threw it obliquely against

the wall, from which it rebounded in an opposite and equally oblique

direction. He then sketched the annexed figure, and proceeded as

follows:--“When I threw the ball against the wall B, in the direction

A B, having struck it, it glanced off, making an angle, in its passage

back again, equal to that which it made in its approach to the wall. If

I draw the perpendicular B D, this fact will be rendered more apparent,

and you will perceive that the angle A B D is equal to the angle C B D:

the former is termed the _angle of incidence_, the latter the _angle of

reflection_; and these angles, remember, are always equal, provided the

ball under experiment be perfectly elastic.”

[Illustration: Diagram showing the physics of rebounding.]

“Do you mean to say,” asked Tom, “that the more obliquely I throw the

ball against the wall, the more obliquely it will rebound?”

“Exactly; that is my meaning: and see whether you cannot explain the

fact, for it depends on the composition and resolution of the forces, a

subject which I should hope you thoroughly understand.”

Tom pondered for some time over the drawing, and at length observed,

that there was one difficulty which he could not immediately surmount.

“State your difficulty,” said Mr. Seymour.

He proceeded to observe, that the force acting in the direction A B

would certainly be resolved into two others, viz. one in the direction

F B, and another in that of D B; “because,” continued he, “these lines

are the adjacent sides of the parallelogram, of which A B is the

diagonal; and I well know that whenever a force strikes obliquely, it

is thus resolved.”

“That is all very well explained,” replied his father; “pray proceed.”

“Now comes the difficulty,” continued Tom; “for the force D B will of

course be destroyed by the wall, and that represented by F B, which is

the only one that can remain, would carry the ball to E.”

“It certainly would do so,” answered his father, “if the ball were

perfectly devoid of elasticity; but remember that, in consequence of

this property, the force D B will be exchanged for one in an opposite

direction, B D.”

“I had entirely overlooked the elasticity,” said Tom; “I now see my way

clearly, for in that case there must be two forces acting in the

directions B D, B E, which will, of course, drive the ball down the

diagonal B C.”

“Your demonstration is perfectly correct, my boy; and I think you will

now admit that I could not have adduced a more beautiful instance of

the composition and resolution of forces; for, in the first place, you

resolve the diagonal force into two others, and then you recompound

these again to produce another diagonal one.”

“But I think you told us that the angles of incidence and reflection

were only equal when the rebounding body was perfectly elastic.”

[Illustration: Diagram showing more physics of rebounding.]

“Clearly so; the force D B must be exchanged for an equal one B D, or

else the angle A B D cannot be equal to the angle D B C; but I will

render this fact still farther intelligible by another diagram. Let B,

as in the former case, represent the wall, upon which the imperfectly

elastic body impinges in the direction A B.--The force will of course

be resolved into two others, viz. into D B and F B; the force D B,

however, instead of being replaced by the opposite one B D, will now be

represented by the shorter line B G; or that of B H or B I, according

to the degree of elasticity. If we, therefore, complete the

parallelogram, B C, B K, or B M will be the diagonal path of the body;

making, as you perceive, the _angle of reflection_ D B C, greater than

that of _incidence_ A B D; and where the body is perfectly inelastic,

the force D B will be wholly destroyed, and, the force B E alone

surviving, the body will be carried along the line B E. I have now,”

continued Mr. Seymour, “explained to you the principal laws which

govern those forces by which your ball or marbles are actuated. It is

true that in practice you cannot expect the results should accurately

coincide with the theory, because, in the first place, you cannot

obtain marbles that are of equal density and elasticity, and of true

figure; and, in the next, there will be obstacles against which it is

impossible to guard. The spinning of the marble will also have a

material influence on its motion, as we have already discovered. In the

game of billiards, where every obstacle is removed, as far as art can

assist, the theory and practice are often strangely discordant. But we

have dwelt sufficiently upon the subject; we will, therefore, return to

the library, where I intend to exhibit an experiment in farther

elucidation of the subject of collision.”

The party accordingly proceeded on their return.

“I hope,” said Mr. Seymour, addressing himself to Mr. Twaddleton, who

was walking a few paces before him, “that the maiden ladies have not

espied their vicar at a game of marbles; if they should, what a

chuckling would there be at their next tea-party!”

“A fig for the spinsters!” exclaimed the vicar, as he hastily turned

round, and arrested the progress of the party by his gesture. “You

really speak, Mr. Seymour, as though it were derogatory to my character

to descend from the more austere pursuits to the simple but innocent

amusements of youth. Let me remind you, sir, that the Persian

ambassadors found Agesilaus, the Lacedæmonian monarch, riding on a

stick.”

“True,” replied Mr. Seymour; “and the ambassadors found Henry the

Fourth playing on the carpet with his children; and it is said, that

Domitian, after he had possessed himself of the Roman empire, amused

himself by catching flies; but these were kings: now I admit that

philosophers are monarchs, but monarchs are not always philosophers;

you must, therefore, produce some less objectionable authority, if you

stand in need of such a sanction. Let me see whether I cannot assist

you; there was Socrates, if tradition speaks truly, who was partial to

the recreation of riding on a wooden horse, for which, as Valerius

Maximus tells us, his pupil Alcibiades laughed at him.”

“I care not who laughs at me,” exclaimed the vicar; “I enjoy the

amusements of youth, and agree with Dr. Paley, in regarding the

pleasure which they are made to afford, as a striking instance of the

beneficence of the Deity; and should you so far relax as to put your

plan into execution, of writing a work upon juvenile sports, I hope you

will call upon me to compose a eulogy, by way of preface.”

“I shall not forget your offer, depend upon it.”

“Did not Archytas,” resumed the vicar,

“‘He who would scan the earth, and ocean’s bound,

And tell the countless sands that strew the shore,’

as Horace says, invent the children’s rattle?--Toys, my dear sir, have

served to unbend the wise, to occupy the idle, to exercise the

sedentary, to moralize the dissipated,”--

“And,” interrupted Mr. Seymour, “to instruct the ignorant.”

“I will also convince you,” continued the vicar, “that the tournaments

were indebted for their origin to the Troy game (_ludus Trojæ_), first

introduced into Italy by young Ascanius.”

The foregoing episode having been concluded, the party proceeded,

without any farther interruption, to the Lodge. On their arrival, Mr.

Seymour produced a piece of apparatus, for the purpose of exhibiting

the experiment he had promised, in illustration of the doctrine of the

Collision of Elastic Bodies.

[Illustration: Two balls, labeled A and B, hanging by strings from a

rod and bouncing against each other.]

“Here are two ivory balls,” said he, “suspended by threads; I shall

draw one of them, A, a little on one side; now I let it go, it strikes,

you see, against the other ball, B, and drives it off to a distance

equal to that through which the first ball fell; but the motion of A is

stopped, because, when it struck B, it received in return a blow equal

to that it gave, and its motion was consequently destroyed. To extend

the experiment, here are six ivory balls hanging in a row; I will draw

the first out of the perpendicular, and let it fall against the second;

see! see! none of the balls appear to move except the last, which you

perceive flies off as far as the first ball fell. I should like to hear

you explain this.”

[Illustration: Six balls hanging by strings from a rod and bouncing

against each other, but with only the two balls on the ends moving.]

Tom observed, that when the first ball struck the second, it received a

blow, in return, which destroyed its motion; and that the second ball,

although it did not appear to move, must have struck against the third,

the reaction of which set it at rest; that the action of the third ball

must have been destroyed by the reaction of the fourth, and so on,

until motion was communicated to the last ball, which not being reacted

upon flew off.

Mr. Seymour commended Tom for his explanation; but he begged him to

understand that such an effect only occurred when the balls were

elastic; and he proceeded to exhibit the difference between elastic and

inelastic bodies by another experiment. “When you raise one of these

inelastic balls, made of clay, out of the perpendicular, and let it

fall against the other, E, the action and reaction not being augmented

by the force of elasticity, are insufficient to destroy the motion of

the former; only part of the motion D will, therefore, be communicated

to E, and the two balls will move together to _d e_, which are less

distant from the vertical line than the ball D was before it fell.”

[Illustration: Two suspended, inelastic balls, labeled D and E ,

showing positions after D collides with E]

Before we close this chapter, we cannot resist the pleasure of

informing our readers that Major Snapwell, in company with his legal

adviser, had quitted Overton, for the purpose of making such

preliminary arrangements as the purchase of an estate must necessarily

require. It is not our intention to accompany them; nor shall we travel

over the plains of parchment, nor wade through the rivers of ink, which

separate the confines of verbal agreement and legal possession; but

claiming the prerogative of authors, we shall dip our wing in the cup

of inspiration, and by a single flourish of our feathered talisman, at

once put the worthy Major in the undisturbed possession of his newly

purchased mansion, and instal him in one of Daw’s most comfortable

elbow-chairs, surrounded by all the luxuries of polished life.

------------------------------------------------------------------------

[Illustration: Two boys causing havoc by upsetting a washerwoman.]

Philosophy in Sport Made Science in Earnest Being an Attempt to Illustrate the First Principles of Natural Philosophy by the Aid of Popular Toys and Sports · 第 10 / 21 章