Mr. Seymour continued--“The various balancing toys will elucidate the nature of the centre of gravity, point of suspension, and line of direction: the seesaw, rocking-horse, and the operation of walking on stilts, will here come in aid of our explanations. The combined effects of momentum and a change in the centre of gravity of a body may be beautifully exemplified by the action of the Chinese Tumblers. The sling will demonstrate the existence and effect of centrifugal force; the top and tetotum will prove the power of vertiginous motion to support the axis of a body in an upright position. The trundling of the hoop will accomplish the same and other objects. The game of bilboquet, or cup and ball, will show the influence of rotatory motion in steadying the rectilinear path of a spherical body, whence the theory of the rifle-gun may be deduced. For conveying some elementary ideas of the doctrine of oscillation, there is the swing. The flight of the arrow will not only elucidate the principles of projectiles, but will explain the force of the air in producing rotatory motion by its impact on oblique surfaces: the revolution of the shuttlecock may be shown to depend upon the same resolution of forces. Then comes the kite, one of the most instructive and amusing of all the pastimes of youth,--the favourite toy of Newton in his boyish days:[[4]]--its ascent at once developes the theory of the composition and resolution of forces, and explains various subordinate principles, which I shall endeavour to describe when we arrive at the subject. The see-saw will unfold the general principle upon which the Mechanical Powers are founded; and the boy may thus be easily led to the theory of the lever, by being shown how readily he can balance the heavier weight of a man by riding on the longer arm of the plank. The theory of colours may be pointed out to him as he blows his soap-bubbles;[[5]] an amusement which will, at the same time, convince him that the air must exert a pressure equally in all directions. For explaining the theory of sound, there are the whistle, the humming-top, the whiz-gig, the pop-gun, the bull-roarer, and sundry other amusements well known in the play-ground; but it is not my intention, at present, to enumerate all the toys which may be rendered capable of affording philosophical instruction; I merely wish to convince you that my plan is not quite so chimerical as you were at first inclined to believe.”
“Upon my word,” said the vicar, “no squirrel ever hopped from branch to branch with more agility,--you are the very counterpart of Cornelius Scriblerus; but I must confess that your scheme is plausible, very plausible, and I shall no longer refuse to attend you in the progress of its execution.
Cedo equidem, nec, nate, tibi comes ire recuso,[[6]]
as Virgil has it.”
Mr. Seymour, however, saw very plainly that, although the vicar thus withdrew his opposition, he was nevertheless very far from embarking in the cause with enthusiasm, and that, upon the principle already discussed, he would perform his part rather as a task than a pastime. Nor was the line which Mr. Twaddleton had quoted from the Æneid calculated to efface such an impression. It was true, that, like Anchises, he no longer refused to accompany him in his expedition; but, if the comparison were to run parallel, it was evident that he would have to carry him as a dead weight on his shoulders. This difficulty, however, was speedily surmounted by an expedient, with which the reader will become acquainted by the recital of what followed.
“I rejoice greatly,” said Mr. Seymour, “that we have at length succeeded in enlisting you into our service; without your able assistance, I fear that my instruction would be extremely imperfect; for you must know, my dear sir, that I am ambitious of making Tom an antiquary as well as a philosopher, and I look to you for a history of the several toys which I shall have occasion to introduce.”
This propitiatory sentence had its desired effect.
“Most cheerfully shall I comply with your wishes,” exclaimed the delighted vicar; “and I can assure you, sir, that, with regard to several of the more popular toys and pastimes, there is much very curious and interesting lore.”
Mr. Seymour had upon this occasion succeeded in opening the heart of the vicar, just as a skilful mechanic would pick a patent lock; who, instead of forcing it by direct violence, seeks to discover the secret spring to which all its various movements are subservient.
“To-morrow, then,” cried the vicar, in a voice of great exultation, “we will commence our career, from which I anticipate the highest satisfaction and advantage; in the mean time,” continued he, “I will refresh my memory upon certain points touching the antiquities of these said pastimes, or, as we used to say at college, get up the subject. I will also press into our service my friend and neighbour Jeremy Prybabel, whose etymological knowledge will greatly assist us in tracing the origin of many of the words used in our sports, which is frequently not very obvious.”