In the course of the ensuing week Mr. and Mrs. Seymour proceeded to offer their congratulations to the new proprietor of Osterley Park. On being ushered into the library, they were not a little surprised and startled by the loud voice of the major, who, addressing Mr. Twaddleton, exclaimed, “Never will I again suspect the antiquity of your rarities, nor question the rarity of your antiquities.” “Offended me!” exclaimed the vicar, “oh no. No, indeed, my dear Major Snapwell; a difference of opinion on an antiquarian subject may excite my regret, and in some cases, as in the present instance, awaken my pity; but it cannot offend me; it can never occasion any feeling like anger: that would be to visit the folly of others upon myself.” “What is the subject of your difference, gentlemen?” asked Mr. Seymour. “The evidences of druidical rites, as deducible from certain cavities to be found in granitic rocks, and which have received the appellation of rock basins,” replied the major. “And of which,” exclaimed Mr. Twaddleton, “I have a most unquestionable specimen, collected by no less a geologist than the curator of the cabinet at Penzance, from that ancient metropolis of the druids, Carn-bre hill.” “I admit,” said the major, “that I never before saw so perfect a specimen; it is as spheroidal internally, as if it had been actually shaped by a turning-lathe.” “And yet, in spite of such evidence,” replied the vicar, “you question its sacred origin, and deny its ever having been used as a pool of lustration.” Mr. Seymour here interposed. “Upon a subject of purely historical difficulty, I might feel diffident in offering myself as an umpire between such learned antiquaries; but, as the origin of ‘rock basins’ involves a geological question, I will venture to deliver an opinion. Depend upon it, vicar, that you are maintaining a position that cannot be defended; these uncouth cavities, together with all the fancied statuary of Borlase(27), “What say you to that, vicar?” triumphantly exclaimed the major. “Oh, impiety, impiety!” cried the vicar;-- “‘Hostis habet muros, ruit alto a culmine Troja,’ as Maro has it. That such glorious monuments, which have so long braved the tempests, should fall under the hammer of these Philistines! Geology, Mr. Seymour, is infidelity in masquerade; remember the mites in the Cheshire cheese, Mr. Seymour, ‘consider their ways and be wise.’” “Philistines as we are, in your opinion,” replied his opponent, “our forges have served to sharpen your weapons against the attacks of infidelity.” “Come, come, gentlemen,” said Mr. Seymour, “the continuance of this discussion can neither amuse nor instruct us. I have, however, some intelligence to communicate which will soothe every feeling of irritation. We have received a letter from Isabella Villers, in answer to an invitation to Overton, and she graciously accepts it, and proposes being with us on Wednesday next.” The major was delighted, and conversed upon various points connected with the intended union of his nephew with that lady, which we do not think it necessary to relate in this place. The vicar and major shook hands, and it was proposed that they should dine at Overton Lodge the following day, and, as a specific overture, that the major should visit the vicarage in his way, and again inspect some of the disputed antiquities of the reverend collector. The following morning was occupied with the consideration of those different toys which are indebted for their operation to the pressure of the atmosphere. “John is, at this moment, amusing himself in the garden with the one which I brought with me from school,” replied Tom. “Then you shall construct another for yourself. Here is leather and string.” “This leather is too stiff; but I may, perhaps, make it answer the purpose by first soaking it.” Having allowed it to remain in water for a short time, the leather became sufficiently pliable for his purpose; he therefore cut it into a circular shape, and affixed a string through its centre. The juvenile party now hastened to the lawn, and having once again dipped his newly-constructed sucker into the water, the ingenious boy placed it upon a stone, pressed down the leather with his foot, and succeeded in making it raise the weight. “Well done, my boy! Now, then, explain the reason of the leather’s adhesion to the surface, and of its being thus capable of retaining its hold, notwithstanding the gravity of the stone.” “In the first place,” answered Tom, “the edges of the wet leather, from being closely pressed, stuck with sufficient firmness to the smooth surface of the stone, to resist the force of the string as I pulled it upwards; the consequence was, that a hollow was formed in the middle part of the leather; and, as that hollow place cannot contain any air, it is called a vacuum.” “Very well,” replied his father, “so far you are right; but you have not informed me in what manner a vacuum acts in preventing the stone from quitting the leather.” “It makes it adhere to it by some kind of suction, but I confess that I do not exactly understand the subject.” “Then let us proceed cautiously and deliberately in the explanation. In the first place, you have said, Tom here acknowledged that he had not before understood the reason of the leather’s adhesion to the stone. “Having, then, settled this point to your satisfaction,” continued Mr. Seymour, “let us proceed. Your idea of a vacuum being formed in the hollow part of the leather is perfectly correct: for, as you draw up the central part by the string, the hollow thus produced must necessarily be a vacuum, since the air cannot pass through the leather to supply it; in this state, therefore, the atmosphere presses upon the exterior of the leather, and like any other weight prevents its rising from the stone.” Fanny and Louisa here expressed some surprise on hearing of the weight of the atmosphere; the former observed, that she did not feel any pressure from it. “Until your explanation,” said Tom, “I really believed that the leather adhered to the stone by some kind of suction, just as the back of my hand adheres to my lips, whenever I place it to my mouth, and draw in my breath.” Mr. Seymour here expressed a doubt whether his son was even yet a perfect master of the subject: he told him that there was no such operation in nature as suction; that it was merely a popular term to denote the action of the air upon a vacuum. “Your hand,” said he, “adheres to your mouth, in consequence of your forming a vacuum within it, by forcibly drawing in your breath, and the resistance which is opposed to its removal arises entirely from the pressure of the atmosphere upon it. Many are the effects which may be explained upon a similar principle. I dare say you well remember the astonishment which you expressed at the force with which the limpets attached themselves to the rocks.” “O yes, papa,” exclaimed Louisa, “I well remember, when we walked on the sea-shore, that, on first touching the limpets, they appeared loose and moveable, but before I had time to remove them, they fastened themselves as firmly as though they had been a part of the rock upon which they were fixed; how could that happen?” “Have you never observed,” asked Mr. Seymour, “the security and ease with which flies frequently walk upon a smooth wall, or a pane of glass, or even along the ceiling, with their bodies downward?” “To be sure,” replied Tom; “but are not their legs provided with some sticky matter, which enables them to preserve themselves from falling?” “That is a popular error, my dear; the fact is, that their feet are provided with little cups, or suckers, which they alternately exhaust and fill with air; by which means they are enabled to walk in every position, over the most slippery surfaces.(28) In like manner, the walrus, or seal, a painting of which you may remember to have seen in the Panorama of Spitzbergen, is capable of climbing the masses of slippery ice with perfect security.” At this moment, Tom’s stone fell from the sucker. Louisa enquired how it could have happened. “The circumstance is to be easily explained,” said her father. “The atmosphere, by its pressure, ultimately forced its way through the edges of the sucker; its interior, therefore, became filled with air, and it consequently balanced the external weight, which had before confined it.” “I think,” said the vicar, “that Tom must now surely understand the theory of the leathern sucker; what say you, my boy? Cannot you exclaim with Persius, ‘Intus et in cute novi.’” “Which I suppose,” observed Mr. Seymour, “you “Exactly,” answered the vicar. “Then never more protest against the vice of punning, for a more atrocious specimen of the lusus verborum was never sported by the most incorrigible Johnian: but, to your classical fancy, any object enclosed in a Latin shrine appears as a deity.” The vicar had just drawn up his person into a suitable attitude for combat, and would, no doubt, have defended himself against this unexpected attack with his usual address, had not a circumstance occurred, which put an abrupt termination to the discourse. “See! see!” exclaimed Louisa; “what can have happened? There is Jerry Styles, with a crowd of villagers, running towards us in the greatest state of agitation and alarm.” “Jerry Styles? It is, indeed, as you say, my faithful clerk,” cried the vicar. “Bless me,--bless me, what can have happened! Is the vicarage on fire? Has the old roof at last tumbled into the chancel?” “Oh, sir!--oh, my dear sir!” vociferated the terrified servant of the church, whose blanched cheeks made his red nose appear like a volcano burning amidst a desert of snows, “poor Tom Plank has blown the roof off his house, and is so dreadfully wounded that it is impossible for him to survive long, if, indeed, he is not already dead.” “How did it happen?” exclaimed several voices. “From a speriment! a speriment! it all came from a flossical speriment!” replied the breathless clerk; “but, pray, gentlemen, come directly to the village; for mercy’s sake, gentlemen, don’t delay a moment.” The vicar and Mr. Seymour instantly proceeded with the terrified Jerry Styles towards the house of the unfortunate “planer of deals;” they had not gone On their arrival at the house, the roof of which they at once perceived had not suffered in the fray, they learned that Tom Plank had been engaged in some experiments for producing a vacuum, in the prosecution of his new scheme of propelling passengers through a funnel; and that, in firing a mixture of oxygen and hydrogen gases, he had neglected the usual precaution, and blown up his apparatus; the stop-cock had been unceremoniously expelled through the window, and, in its passage, had ungraciously flown in the face of its master, and left the traces of its indignation in the form of a very slight scratch upon his forehead; this accident, with a burn of the fingers, was the only personal injury he had sustained. “Come, come,” said Mr. Seymour, “no mischief has occurred, and the accident will, I trust, teach you more caution for the future. You are not the first adventurer who has burned his fingers by bubble speculations, and in vain attempts to raise the wind.” Dr. Doseall, however, with a countenance of stern composure, and a portentous shake of the head, maintained that the accident was by no means so trifling as Mr. Seymour appeared to suppose; and, in conformity with this view of the case, he had prudently bled his patient largely, and directed sundry mixtures and lotions, together with a quantum sufficit of laudanum, in order, as he said, “to keep down the swelling and puffing of the head,” although there were those present who were uncharitable enough to hint, that the swelling and puffing related rather to the Doctor’s bill and character, than to the patient’s pericranium. After a short interval, engaged in answering the numerous enquiries of the anxious spectators, the doctor, with an air of awful solemnity, advanced to the sufferer, “Avaunt!” exclaimed Mr. Seymour, “do you suppose that Tom Plank has the throat of the great dragon which the Indians believe to swallow the moon, and thus to produce the phÆnomena of lunar eclipses? Away with thy treacle and pipe-clay; there cannot be the least pretext for this parade of remedies; I warrant you that Dame Nature, unless she be put out of humour by your officious interference, will heal the scratch before to-morrow’s sunrise.” The doctor, as our readers will readily imagine, was very justly incensed at this ex-professional interference. His first determination was to treat the matter as a joke, and to turn the laugh against the unmannerly intruder; but the abortive smile was strangled in its birth, and suffused the hue of death over his visage. Never did a countenance, in the focus of his blue window bottle, by candle-light, exhibit a more ghastly pallor; and we can scarcely predict what might have been the consequence, had he not instantly administered a consoling cordial to his nostrils; for, be it known, that the doctor took snuff in the same extravagant proportion as his patients took physic. Having by these means recovered his self-possession, he instantly seized his cane, and waving it with as much dignity as Jove is said to brandish his thunder, he departed in deep dudgeon, which was betrayed by a snarl, not unlike that of a hungry dog who is unexpectedly despoiled of a savory bone, and by a contortion of the face, similar to that we have observed in a child who has unfortunately mistaken Aloes for Liquorice. No sooner had the man of wrath and phials retreated from the field of blood, than Mr. Twaddleton advanced to the suffering artist, deeming the moment of bodily fear as affording a favourable opportunity As the party left the house, they met Mrs. Seymour, with Tom and Louisa, whose looks sufficiently testified the anxiety they had suffered. “Is it all over? Is he dead?” asked Mrs. Seymour. “No, no; he is quite safe; it was an extremely slight accident, although Doseall wished us to believe that it was likely to terminate in some dreadful manner. The vicar thinks that it may prove the means of driving science out of Tom Plank’s head, and I intend to make it subservient to driving it still farther into ours.” “What do you mean?” cried Tom. “I mean that it was an extremely apposite accident for illustrating the subject upon which we were engaged at the moment of interruption.” “This is the second accident then,” observed “Knowledge, my dear girl, is not promoted by the opportunity of seeing, but by the faculty of skilfully observing, and reflecting upon what we see; were it otherwise, the merit of a traveller might be at once estimated by the number of shoes he had worn out. Whenever, therefore, you hear of a discovery having been made by accident, do not, on that account, depreciate the merits of its author. It is certainly true, that many an important truth has been brought to light from some casual observation(29), but the dexterity with which such observation was applied constitutes the merit of the discoverer. Well, but to show in what manner the accident of Tom Plank bears upon the subject under discussion:--He had ignorantly fired a quantity of oxygen and hydrogen gases in a tin vessel; the consequence of the combustion was the immediate formation of a vacuum: and what happened? Why, the pressure of the external air, not being any longer balanced by elastic matter in the interior of the apparatus, crushed it with violence, as any other enormous weight might have done; and so ended the accident, which report magnified into a most awful catastrophe.” As the party proceeded on their way home, they continued to discourse on the subject of the air’s pressure. “If the atmosphere exerts so enormous a pressure, and has so much weight,” observed Louisa, “it is strange that it should not fall down on the earth.” Mr. Seymour replied, “that the air was a peculiar fluid, which, from its elastic properties, was distinguished by the term of an elastic fluid, the particles of which were too far distant from each other to exert any cohesive attraction amongst themselves.” “And so it actually does,” replied Mr. Seymour. “The lower stratum of the atmosphere rests upon the ground, but the strata above it do not fall, because they are supported by the particles beneath them, in the same manner as the water at the surface of a basin is supported by that at the bottom: the only difference in these two cases arises from the one being an elastic, and the other an inelastic fluid; so that the air after compression resumes its original dimensions; and since the atmosphere, by the action of gravity, is always in a state of compression, so is it always endeavouring to expand itself.” “If, then, the force of gravity were diminished,” observed Louisa, “the air would become much lighter, and I suppose that is the true reason of its being so much less dense in the upper regions.” “Scarcely,” replied her father. “Have you forgotten the explanation “I recollect it perfectly,” exclaimed Tom; “and it explained to us the reason that a marble fell from the top of a house, and from the ball of St. Paul’s with the same velocity.” “And yet I am quite sure,” said Louisa, “that I have lately read an account of the air being so extremely light upon the top of a high mountain as to affect the breath and occasion great uneasiness.” “I do not deny the fact, my dear; I only question your explanation of its cause. Can it not, think you, be accounted for upon some other principle than that of the diminished force of gravity?” “The fact, then,” said her father, “is simply this; since the air is elastic, or capable of yielding to pressure, so, of course, the lower parts must be more dense, or in a greater state of compression than those which are above them. In a pile of fleeces of wool, are not the lower fleeces pressed together by the weight of the superior ones, and do they not lie light and loose, in proportion as they approach the uppermost fleece, which receives no external pressure, and is confined merely by the force of its own gravity?” “Clearly,” said Louisa. “Well then, we will suppose, for example, that the whole column of the atmosphere were divided into a hundred parts, and that each of these parts weighed an ounce; would not the earth, and all things on its surface, be, in such a case, pressed upon with the whole hundred ounces?” “No one can deny that,” said Tom. “The lowest stratum of air,” continued Mr. Seymour, “would be pressed upon by the ninety-nine ounces above it; the next by ninety-eight; and so on, until we arrived at the ninety-ninth stratum from the bottom, which would, of course, be subjected to no more than one ounce of pressure, or to the weight of the last and highest stratum.” The children were perfectly satisfied with this simple explanation; and Tom enquired whether, for the same reason, the water at the bottom of the sea must not be very dense, and unlike that we are accustomed to observe on the surface: his father, however, corrected this notion, by stating that water, not being, like air, elastic and compressible, would not suffer any material diminution in volume, although pressed even by the enormous weight of the superincumbent ocean.(30) “I have before alluded to the relative compressibility of air and water, and the present appears a good opportunity Bottle Imps “Why, the spirit of Simon Magus must surely possess thee!” exclaimed the vicar. The children, as may be readily imagined, were much astonished at so singular an effect, and expressed much anxiety to be informed by what mechanism it was produced. Their father accordingly proceeded with the following explanation. “I have here,” said he, “a figure exactly similar to those in the bottle, which we will now examine. You will observe, that in its centre there is a cavity terminating in a small orifice in the lower part; this cavity may be made to contain any quantity of air, so as to give the required buoyancy to the figure: now mark!--I press my hand upon the parchment cover, and the figure, you perceive, descends; I now remove the pressure, and see, it immediately reascends. The water in the bottle, as I have told you, is incompressible; when, therefore, I press upon the surface, it rises into the interior of the figure, and, consequently, by compressing the air into a less space, renders it less buoyant; but no sooner is the hand removed, than the enclosed air resumes its former volume, and expels the intruding water; in consequence of which the figure regains its former lightness, and reascends. Do you understand me?” asked Mr. Seymour. “Well, then,” continued Mr. Seymour, “you will now understand the use of the air-bladder in fish, for it is constructed upon a precisely similar principle. When the fish desires to descend, it presses upon the bladder by means of its muscles, and thus condenses the included air into a smaller volume.” “I now also perceive why the water at the bottom of the sea cannot be much more dense than that on the surface; but, if we could dig a pit to the centre of the earth, the air, in that case, would be highly dense, because, unlike water, it is compressible,” said Tom. “The density of the air,” replied his father, “would, undoubtedly, materially increase as we descended. It has been calculated that, at the distance of thirty miles below the surface, the air would have the same density as water; and, at the depth of forty-two miles, that of quicksilver; while, at the centre, it would be more solid than any substance of which we have any idea, for its density would be thousands of millions of times greater than that of mercury.” Mr. Seymour then informed his young pupils, that after the lesson they had just received, they would never again be puzzled by the motions of the barometer, which had so often excited their wonder. “As the quicksilver is contained in a closed tube, I do not exactly understand how the air can act upon it; and if the tube were not closed, it would of course run out from its weight,” observed Louisa. “You are altogether in error,” said her father. “In the first place,” he continued, “I will show you that the bulb at the lower extremity of the tube is open, in order that the quicksilver may freely communicate “That I understand: but what can cause the pressure of the air to vary at different times?” asked Tom. “Cannot you imagine the atmosphere to be an airy ocean, and to be therefore thrown into enormous waves, so that we may sometimes have a longer column of air above us than at other times; this is one explanation, there may be other causes not so intelligible,” answered Mr. Seymour. “But enough of this for the present. Now, before we quit the subject of the air’s elasticity, let us consider the philosophy of the pop-gun; an amusement with which, I have no doubt, you are well acquainted.” “Indeed I am, papa; but do you allude to the quill, or to the wooden pop-gun?” “The principle in both is the same; tell me, therefore, the origin and nature of the force which enables you to shoot your pellet to so considerable a distance.” “It depends upon the action of the air,” replied Tom. “Undoubtedly: but your answer is too general; I wished you to state, in precise terms, the changes which the air undergoes upon this occasion. You first ram in your pellet to the further end of the tube, do you not?” “To be sure; and then I drive in a second pellet, “Very well: now examine what takes place; on propelling forward your second pellet, you condense the air which is enclosed between the two, until its elastic force becomes so great as to overcome the friction of the first pellet; thus released, the air expands with considerable force, and imparts a rapid motion to the pellet.” “I have frequently heard of the air-gun,” said Louisa; “I suppose it depends upon a similar principle.” “It does; and it affords a very striking example of the surprising force which air is capable of exerting, when condensed to a considerable degree; for, by means of this instrument, bullets may be propelled with a force very nearly equal to that of gunpowder.” “It is a curious fact,” observed the vicar, “that although the air-pump is a modern invention, yet the air-gun, which is so nearly allied to it in the construction of its valves and condensing syringe, should have existed long antecedent to it; for it is recorded that an air-gun was made for Henry IV. by Marin, of Lisieux, in Normandy, as early as 1408; and another was preserved in the armoury at Schmetau, bearing the date of 1474.” “But the air-gun of the present day,” said Mr. Seymour, “is very different from that which was formerly made, and which, like the pop-gun, discharged but one bullet, and that after a long and tedious process of condensation, while it is now made to discharge five or six without any visible variation of force, and will even act upon a dozen, but with less effect.” “I feel very curious to learn something more about this air-gun,” said Tom. “There is a reservoir for the condensed air,” replied Mr. Seymour, “which is secured by a nicely “But how is the condensed air introduced into the reservoir?” asked Tom. “By means of a condensing syringe,” replied his father; “but I will take an opportunity of exhibiting the instrument in operation.” The reader will be pleased to recollect that the major agreed to pay a passing visit to the vicarage; it now becomes our duty to record what happened upon that memorable occasion; and we, perhaps, cannot better represent the nature of the discussion that took place than by relating the account as it was given by the belligerent parties themselves in conversation with Mr. Seymour. “Well, gentlemen,” said Mr. Seymour, “is it peace or war? I trust you have amicably adjusted all your differences.” “Upon my word,” answered the vicar, “I have just reason to complain of the major’s unjustifiable scepticism upon points that are perfectly unquestionable.” “You continue then to smart under the major’s stinging criticisms, ‘majore sub hoste.’ There is a Latin pun for your consolation,” said Mr. Seymour. “The vicar alludes, I suppose,” said the major, “to the doubt I expressed respecting the authenticity of his leathern money?” “That is one of the many subjects upon which, I must say, you have betrayed a deficiency in historical knowledge. Seneca informs us that there was anciently stamped money of leather; and the same thing was put in practice by Frederick II. at the siege of Milan; to say nothing of an old tradition amongst ourselves, that, in the confused times of the barons’ wars, the same expedient was practised in England.” “And yet you doubt the authenticity of my leathern money, which I am fully persuaded was coined in 1360, by John, king of France, who, having agreed to pay our Edward the Third the sum of 3,000,000 golden crowns for his ransom, was so reduced as to be compelled to a coinage of leather for the discharge of his household expenses.” “I have only questioned the authenticity of that specimen which I saw in your cabinet,” replied the major: “and so must any person who views it through a medium unclouded by prejudice. I will stake my whole library to a horn-book, that our friend Mr. Seymour will agree with me in pronouncing it a fragment of the heel of an old shoe: let him observe the perforation, and say, if he can, that it has not been produced by a nail or peg. But really, my dear Mr. Twaddleton, you have forced me, much against my inclination, into this controversy.” “Very good, sir! very good! the heel of an old shoe, forsooth! But I thank you, Major Snapwell,” exclaimed the vicar with some warmth; “I thank “Assuredly,” said Mr. Seymour, with a wicked smile; “I dare say there may be numerous holes in this leathern coin; for many have been the antiquaries who have, doubtless, pinned their faith upon it.” “Psha, psha!” cried the vicar; “for once, at least, Mr. Seymour, let me entreat you to be serious; the subject, sir, is important, and merits your respect. It is from that very hole that I am enabled to identify the coin: yes, major, from that very hole, which you affect to despise, I am enabled to derive its principal claim to antiquity. Are we not expressly informed, that the leathern money of John of France had a little nail of silver driven into it?” “Well, then,” continued the major, “what say you to that tell-tale stitch, which I so unfortunately picked out with my penknife?” “Admirable ingenuity! most refined sophistry! provoking perversion!” exclaimed the vicar. “It is really amusing to observe the address with which the prejudiced observer distorts every fact to his own advantage. Why, bless me, sir, that stitch is strong enough to drag fifty such opponents out of the slough of unbelief.” “Do explain yourself,” said Mr. Seymour. “Explain myself! the stitch speaks for itself, sir. Were not these leathern coins strung together in different numbers, to facilitate payments? For, you will admit, that it would have been extremely inconvenient to have coined single pieces of leather, of different denominations. But stop, sir, stop; look at this, look at it, major, with care and attention. That,” said the vicar, as he drew a small coin out of his waistcoat pocket with an air of imperturbable gravity and self-satisfaction, The dinner was announced before the conclusion of the discussion; and as the reader will probably agree with us in thinking that a question of such grave historical importance ought not to be decided without due care and deliberation, we shall afford the disputants a reasonable time for reflection, and put an end to the chapter. 37.In the cod-fish the air bladder is familiarly called the sound. Two boys blowing bubbles from tobacco-pipes.
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