to his English coins. "This," said he, "is a shilling of Henry VII., curious as being the first shilling ever struck; it was presented to me by a college friend some years ago, and I have been lately informed that it is so rare as to fetch twenty-five pounds; but let me beg you to examine attentively this curious little treasure," said the vicar, his eyes twinkling with pleasure as he placed the dainty morsel in the hand of Mrs. Seymour; "it is," continued he, "a silver groat of Perkin Warbeck; on one side are the Royal arms, but without a name; they are surmounted, you perceive, with an arched crown, and placed between a fleur-de-lis and a rose."

"What is the inscription ?" asked Mrs. Seymour.

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Say legend, Madam, if you please; the words are, 'Domine, salvum fac regem,' the date 1494. The coin is supposed to have been struck by the order of the Duchess of Burgundy for Perkin Warbeck, when he set out to invade England."

"Pray," said Tom, "have you got a Queen Anne's farthing?"

"It is really curious," observed the vicar, "that well-informed persons should still continue to be deceived with regard to the value of this coin. The absurd notion of its being worth 100l. arose from an advertisement of an old lady, who had lost one, stating it to be one of the only three known in the world, and worth at least 100l. The truth is, I understand from my much-valued friend of Tavistock Street, that these farthings generally fetch from five to twenty shillings each; there are several different types of them, but the only one intended for currency is that bearing the date of 1714; all the others were struck as patterns. This is certainly scarce, in consequence of the death of the Queen taking place before the coinage was finished. The farthing and sixpence of Oliver Cromwell are much more scarce and valuable, the one generally brings 10l the other as much as 251. It appears that, after Oliver had stamped his head upon them, he was afraid to issue them as current coins, which accounts for the few which have been handed down to us." “ You remind me,” said Mr. Seymour, “ of a story Ilately heard of a crown-piece of Oliver selling at a public auction for as much as two hundred guineas can it be possible?" "You labour under a mistake," answered the coin you allude to is known amongst collectors by the name of the Petition crown of Charles the Second, and it is un

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vicar;

"the

CHAPTER III.

MOTION-ABSOLUTE AND RELATIVE.-UNIFORM, ACCELERATED, AND RETARDED VELOCITY.-THE TIMES OF ASCENT AND DESCENT ARE EQUAL. -VIS INERTIÆ. · FRICTION. - ACTION AND RE-ACTION ARE EQUAL AND IN OPPOSITE DIRECTIONS. MOMENTUM DEFINED AND EXPLAINED. -THE THREE GREAT LAWS OF MOTION.

"THE table-cloth is removed,” cried Tom, as he cast a sly glance through the open window of the dining-room.

"It is, my boy," replied Mr. Twaddleton; "Diffugere nives, as the poet has it."

"Et redeunt jam gramina campis," added Mr. Seymour, archly, as he pointed to the verdant luxuries with which the table was covered.

"Et decrescentia flumina prætereunt," continued the vicar, with a smile, as he passed the nearly exhausted bottle; "but psha! enough of wine and quotation. Come, let us join the children."

Mr. Twaddleton, accompanied by Mr. and Mrs. Seymour and Louisa, rose from the table, and proceeded to the lawn. "The gravitation of Tom's ball," said Mr. Seymour, "furnished an ample subject for our morning's diversion; let us try whether its other motions will not suggest further objects of inquiry."

"I well remember," observed Louisa, "that Mrs. Marcet extols that apple, the fall of which attracted the notice of Sir Isaac Newton, above all the apples that have ever been sung by the poets and she declares, that the apple presented to Venus by Paris; the golden apples through which Atalanta lost the race; nay, even the apple which William Tell shot from the head of his own son, cannot be brought into comparison with it."

"Well said! Mrs. Marcet," exclaimed Mr. Seymour; แ upon my word, had the mother of mankind used but half such eloquence in praise of an apple, we cannot wonder at its influence."

"What honours, then," continued Louisa, "shall we decree to Tom's ball, if it instructs us in the first principles of philosophy ?"

you exacuy comprehend what was

Sul, conunued he, “ean you tell me bout wmen all its other parts involving body was an imaginary line.

observed Mr. Seymour, and so saving.

"I perceive your meaning," said Tom.

"To prevent confusion, therefore, in our ideas, it became necessary to distinguish these two kinds of motion from each other by appropriate terms; and, accordingly, where there has been an actual change of place, in the common meaning of the term, the motion which produced it is termed ABSOLUTE motion; whereas, on the contrary, when the situation has been only relatively changed, by an alteration in the position of surrounding bodies, the motion is said to be RELATIVE."

Surely, , papa," said Louisa, "no person can ever mistake relative for absolute motion; what then is the use of such frivolous distinctions? When a body really moves, we can observe it in the act of changing its place, and no difficulty can arise about the matter."

"Nothing, my dear, is more fallacious than our vision; the earth appears motionless, and the sun and stars seem as if they revolved round it; but it is scarcely necessary for me to inform you that our globe is constantly moving with considerable velocity, while the sun remains at rest. - - Mr. Sadler, the famous aëronaut," continued Mr. Seymour, “informed me, that he was never sensible of the motion of the balloon in any of his excursions, but that, as he ascended into the air, the earth always appeared as if sinking beneath him, and as he descended, as if rising to meet him."

Mr. Twaddleton here observed, that he had heard a very curious anecdote, when he was last in London, which fully confirmed the truth of Mr. Sadler's statement. "An aëro

naut," said he, "whose name I cannot at this moment recollect, had recently published a map of his voyage, and, instead of proceeding in any one line of direction, his track absolutely appeared in the form of circles, connected with each other like the links of a chain: this occasioned considerable astonishment, and, of course, some speculation, until it was at length discovered that his apparent journey was to be attributed to the rotatory motion of the balloon, which the voyager, not feeling, had never suspected."

"And what," asked Tom, "could have been the reason of his not having felt the motion ?"

His father explained to him, that we are only conscious of being in motion when the conveyance, in which we are placed, suffers some impediment in its progress. "If," "said you were to close your eyes, when sailing on calm water, with a steady breeze, you would not perceive that

he, "