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This is the first occurrence in these lessons of the important combination gl. It has two different sounds. When it is not followed by the letter i it has the sound of gl in gland, glebe, glory, glue; and this sound can offer no difficulty. But when the combination gl is followed by the letter i and one of the vowels a, e, o, and u, it is pronounced precisely as the double (1) in the French words bouilli, fille, gresiller, grenouille, bouillon, billard, billet, brouillon, feuillu, and, generally speaking, in all those words where the ll has after the vowel i a squeezed sound in the French language. They who are unacquainted with French may form a notion of this sound by separating and inverting the gl in the enunciation, i.e., by pronouncing before the g, and changing the latter into y. Only the first I must go to one syllable, and the second l along with the y, and with a squeezed sound to the beginning of the next, while care must be taken that the voice should glide rapidly from one syllable to the other, by which means a more equal distribution of the squeezed sound ly will be produced, and a correct pronunciation of the gl effected. An approximation to this sound may be found in the English words million, miliary, biliary, billiards, seraglio, intaglio, and oglio. The letter i, between the combination gl and the vowels a, e, o, and u, is (as well as in the combinations cia, cio, ciu, and gia, go, giu) a mere auxiliary letter, i.e., a mere soundless, written sign, to indicate that-gl before a, e, o, and u is not to have the sound of gl in gland, glebe, glory, and glue, but that squeezed sound, the imitation and description of which I have here attempted.

For example: taglio (váhl-lyo), a sieve; meglio (mêl-lyo), better; piglio (píl-lyo), I take, seize; miscuglio (mis-kóol-lyo), mixture; svegliare (zvel-lyah-rai), to awake; togliere (tôl-lyai-rai), to take away; scegliere (shél-lyai-rai), to choose; doglia (dôl-lyah), sorrows; bigliardo (Lil-lyáhrr-do), billiards; biglietto (bil-lyét-to), note, bill; imbroglione (im-brol-lyó-nai), a meddling fellow; fogliuto (fol-lyoó to), full of leaves. Egli, he, eglino, they, quegli, that one, gli (the plural of the article or the pronoun), with its numerous compositions, and gli, the final inflexion or terminational syllable of nouns and verbs, have always the squeezed sound Uyee; while the mere avllable gli, at the commencement and in the middle of words, always has the sound of gl in gland, glebe, &c. The only exception is Angli, Englishmen, pronounced áhn-glee. For example: figli (fil-lyee), sons; fogli (fol-lyee), leaves of paper; gigli (jil-lyee), lilies: negligerc (nai-gleé-jai-rai), to neglect; negligente (naiglee-jên-te), negligent; negligenza (nai-glee-jên-tsab), negligence; negligentare (nai-glee-jen-táh-rai), to neglect.

ANSWERS TO CORRESPONDENTS.

CIVIS (Dublin): We recommend him to take up Part I. of the French Lessons from the P. E. to follow the Lessons from the W. M. F.. Part II. of the former will be ready in about three weeks.-AMBITION (Copthallcourt) will see the studies that it will be necessary for him to take up, if he wishes to matriculate at the University of London, in vol. ii. of the P. E., p. 137.

EIPSELLIG (Leicester): Right-CARMONEY (Belfast) will see by the solution we have inserted that his is wrong. Thanks for his other communications.-SPEUDE BRADEOS (Fetter-lane): His conjecture about the Greek extract is right; but that about the Greek lesson is wrong. There is a very considerable difference between the ancient and the modern Greek. We believe that old Homer would not be understood in his own country.-J. MILLS (Tewkesbury): His poetry is good, but not sufficiently measured; that is, put into the proper number of syllables in each line; some lines have ten syllables, some twelve, and so on. Were we to correct it, we would begin thus:

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"Ah, dost thou gaze upon that little child,
And smile with admiration at its form?
Scarcely as yet unfolded, helpless thing,
What is there in its features so divine,
Or in its wondrous structure so profound?
This is but one of Nature's lovely works,

With which earth teems throughout her wide domain.
Behold the smallest insects far surpass,
In texture delicate, this blooming child!
Their microscopic organs how minute,
Their mechanique, how wonderfully fine!
But ah, within that infant form there lies
A soul divine; a young immortal soul!
A soul of worth so infinitely great,

That all the powers of Mathematic lore
Its value cannot calculate or weigh."

A. RICHARDSON (Newcastle) and E. EVANS (Ashby-de-la-Zouch): We regret that we cannot give them the information they require.-W. X. (Manchester) and PARALLAX: We advise them to write to Messrs. Watkins and Hill, 5, Charing-cross, London, who will furnish them with a catalogue

of their telescopes, achromatic and reflecting, with their sizes, powers, and prices. They can also have information from the same firm about magic lanterns, sliders, and diagrams or atlases of the heavens.

C. B. C. (Hull) must study our Lessons in Penmanship, vol. ii., P. E.T. MUXLOW (Sheffield): Get an old copy of Barrow's Euclid (which you may at any old book-stall for 1s.), and you will see all the books of Euclid from the 1st to the 15th inclusive.--W. HADFIELD (Hayfield): We know of no paper in which excise vacancies are advertised.-W, J. OSBORNE (Soho): We think that the courtesy is due to any clergyman who does not wish his sermon taken down in short-hand, to refrain from so doing; he is the best judge of the value of his own productions.-J. ADDER (Grandtully): The rule for finding the index of the quotient is this: Subtract the index of the dividend from that of the divisor, and the remainder is the index of the quotient; now this being done for the first term in every step of the operation for finding the greatest common measure, there can be no difficulty at the end, for the remainder will take the indices of its terms from those which correspond to them in the dividend, supposing them, of course, to be in arithmetical progression proceeding from that of the first term.

T. TAIT (Glasgow) should attend to the directions given in No. 36, vol; ii.-N. P. P. should apply to the superintendent of the docks where he wishes to be admitted.-W. R. E. (Gray's-inn-road) and A SUBSCRIBER are informed that Mr. Cassell has published the very book they want, "The People's Biographical Dictionary," compiled by Dr. Beard, and that it may be had at this office for 2s. 4d. in paper covers. The Atlas is progressing in the P. E. Lord Byron swam the Hellespont. Don't bind the " Magazine of Art," or any other periodical, too soon; sell your copy and buy another, taking more care next time.-J. BEWLEY (Langrigg): His verses are very good, but not up to our mark.-A TROUBLESOME SUBSCRIBER will find an article on shell-cleaning in the P. E. Latin wards," col. 2, p. 288, vol. il., should be "Latin words" certainly. STUDENT OF ANGLESEA: In the passage "si cupis placere magistro," the "si" means only if; "cupis" means you desire, as shown by the termination "is;"" placere," to please, according to the Latin idiom, requires the dative "magistro," to the master, to follow it; but we cannot literally say in English, to please to the master: yet, as to please means to give pleasure, we can say to give pleasure to the the body; but the neglect of washing the body, which is a great sin, master. Death would be the consequence of the stopping up the pores of besides being a great evil, is compensated for, in strong and healthy persons, by copious and heavy perspiration, which literally washes the body itself, be long continued with impunity.-CHEMICUS (Falkirk): Mr. Cassell is and clears the pores for a time. Still this is an unhealthy state, and cannot about to publish a work on Botany.

LITERARY NOTICES.

GERMAN.

CASSELL'S GERMAN PRONOUNCING DICTIONARY, in Numbers, 3d. each, or Parts, 1s. each. The entire work will be issued at 8s. 6d. in strong binding. CASSELL'S LESSONS IN GERMAN. Part I., price, 28: in paper covers, or 2s. 6d. neat cloth. Part II. will shortly appear. CASSELL'S LESSONS IN GERMAN PRONUNCIATION. Price 1s. 6d. in paper covers, or 28. neat cloth, will shortly be issued. CASSELL'S ECLECTIC GERMAN READER, price 2s. in paper covers, or 2s. 6d. neat cloth.

CASSELL'S ELEMENTS OF ARITHMETIC (uniform with Cassell's EUCLID) is now ready, price is. in stiff covers, or 1s. 6d. neat cloth.-KEY, 3d.

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ON PHYSICS OR NATURAL PHILOSOPHY

No. VIII.

HYDROSTATICS.

The Science of Liquids at Rest.-Hydrostatics is that part of natural philosophy which has for its object the investigation of the conditions of equilibrium in liquids, and of the pressures which they produce, either in mass, or on the sides of the vessels which contain them. The science which treats of the motion of liquids is called Hydrodynamics; and the application of its principles to the art of conveying and raising water is particularly denominated Hydraulics.

This plate is furnished with a funnel-pipe at R, by which tae water is admitted into the cylinder, and with an air-tight pump-body and piston, the latter being moved up or down by means of a screw P. In the interior of the apparatus is contained a glass reservoir A, filled with the liquid whose compressibility is to be ascertained. This reservoir terminates in a bent capillary tube, the lower end of which is immersed in a mercurial, bath at o. This tube is previously divided into parts of equal capacity, it having been ascertained how many of these parts the reservoir A contains; this is found by determining the weight P of the mercury contained in the reservoir A, and the weight p of the mercury contained in a certain number n of the divisions of the capillary tube; then, denotGeneral Character of Liquids.-It has been already stated the reservoir by N, we have the following proportion p: P:: ing the number of the divisions of the small tube contained in that liquids are bodies of which the particles, in consequence: N; whence, the value of N can be easily deduced. of their extreme mobility, yield to the slightest effort made to displace them. Their fluidity, however, is not perfect; for among their particles there always exists an adherence which constitutes a greater or less degree of viscosity (stickiness). The fluidity of liquids is manifest, but in a higher degree, in the gases; the distinction between liquids and gases being, that the former possess the property of compressibility in a very slight degree, whereas the latter are highly compressible and

elastic.

The fluidity of liquids is shown by the facility with which they take all kinds of shapes; their small compressibility is proved by the following experiment.

Compressibility of Liquids.-Subsequently to the experiment of the academicians of Florence formerly mentioned, liquids were for a long time considered to be incompressible. Afterwards, experiments were made on this subject, in England by Canton in 1761, and by Perkins in 1819; at Copenhagen, by Ersted in 1823, and again by Colladon and Sturm in 1827. From these various experiments, it has been concluded as a fact that liquids are really compressible.

The apparatus employed in measuring the compressibility of liquids are called Piesometers, that is (from the Greek), Pressure-measurers. The following is a description of that of Ersted, with the improvements of M.. Despretz. This piesometer, fig. 19, is composed of a very strong glass cylinder, about 34 inches Eig. 19.

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In the interior of the cylinder is contained a Manometer (rarity measurer) of compressed air. This is a glass tube B, closed at the upper extremity, and open at the lower extremity, which is also immersed in the mercurial bath o. When the tube B is completely full of air; but when pressure is no pressure is applied to the water which fills the cylinder, applied to the water in the cylinder, by means of the screw P and the piston to which it is attached, this pressure is comcompressing the air contained in it. municated to the mercury, which then rises in the tube в by placed alongside of the tube, indicates the quantity by which A graduated scale c, the volume of air is diminished; it is by means of the quantity of diminution in the volume of air that the pressure on the liquid contained in the cylinder is determined, as will be afterwards shown.

is first filled with the liquid whose compressibility is to be In making experiments with this apparatus, the reservoir A found; the cylinder is then filled with water by means of the funnel-pipe R. The screw P is then turned so as to make the piston descend and produce a pressure on the water and the mercury contained in the cylinder; this pressure not only raises the mercury in the tube B, but also in the capillary tube fastened to the reservoir A, as shown in the figure. The rise of the mercury in the capillary tube shows that the liquid contained in the reservoir has diminished in volume the measure of its diminution being indicated on the tube itself, as above mentioned.

In his experiments, Ersted supposed that the capacity of the reservoir remained invariable, and that the sides of it were equally acted upon by the liquid both in the interior and on the exterior. Mathematical investigation has proved that this capacity is diminished by both pressures. In their experiments, Colladon and Sturm took this change of capacity into account; and they have proved that for a pressure equal to that of the atmosphere, and at the temperature of 32° Fahrenheit, the parts of the original volume by which certain liquids were contracted, are as follows:

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They also observed that in the case of water and mercury, within certain limits, the diminution of volume is proportional to the pressure.

Principle of Equality of Pressure.-On the supposition that liquids are incompressible and possess perfect fluidity, and are freed from the action of gravity, the following principle, called the principle of equality of pressure in every direction, universally holds good: liquids communicate in all directions, with the same intensity, the pressures applied to any point of their mass. This principle was first announced to the world by the celebrated Pascal, who died in 1662, and is sometimes called the principle of Pascal.

In order to have a proper idea of this principle, suppose a vessel, fig. 20, of any shape whatever, to be filled with water, aud that in its sides at different places cylindrical openings A, B, C, D, and E are made, to which there are applied moveable pistons exactly fitting them. If to any, piston A, an external pressure be applied, say of 20 pounds this pressure is instan taneously communicated to the internal surfaces of the pistons

86

B, C, D and E, and they will be pushed outwardly with a pres- | the direction m P, may be decomposed into two forces, the one sure of 20 pounds, if their surfaces be each equal to that of the Fig. 20.

E

piston A; but if their surfaces be twice, thrice, or four times that of the piston Athe pressure communicated will be 40, 60, or 80 pounds accordingly; that is, the pressure communicated increases proportionally to the surface.

The principle of equality of pressure is generally considered as a consequence of the constitution of liquids. It can be proved by the following experiment that the pressure is really communicated in all directions; but it does not prove that it is equally so. A cylinder. fig. 21, in which a piston Fig. 21.

a, acting in the direction ma perpendicular to the surface A B, and the other F, acting in the direction mr or BA. The first force a will be counteracted by the resistance of the liquid mass, and the second F will urge the particle m in the direction m F. The same reasoning being applicable to every particle of the liquid surface, it is evident that this surface cannot remain at rest in the direction B A inclined to the horizon, but must assume the horizontal direction, when the force acting in the direction B A becomes zero.

If the liquid be acted upon by other forces besides that of gravity, its surface will tend to take a direction perpendicular to that of the resultant of all these forces, as will be seen in the case of the phenomena of capillary attraction. According to the principle explained above, when a liquid is contained in a vessel or basin of small extent, its free surface is plane and horizontal, seeing that at every point of that surface the direction of gravity is then the same. This is not the case, however, in the surface of a liquid of great extent, such as that of the sea. For the surface of the sea being everywhere perpendicular to the direction of gravity, and this direction varying in different places considerably apart from each other, it is plain that the surface of the sea changes its direction with that of gravity; and the latter being constantly directed to the centre of the earth, the former causes the sea sensibly to assume a spherical form, as may be observed in the phenomena of a ship approaching to, or receding from, the shore.

PRESSURE IN LIQUIDS RESULTING FROM THE
ACTION OF GRAVITY.

Laws of Vertical Pressure Downwards.-If we suppose a liquid to be in a state of rest in a vessel, and imagine it to be divided into horizontal layers of equal thickness, it is plain that each of these supports the weight of all the layers which are above it. Throughout the liquid mass, therefore, we see that gravity gives rise to pressures which vary from layer to layer, and from point to point. These pressures, which come under our consideration in their effects on the bottom and sides of vessels, are subject to the following general laws:

1st. The pressure on every layer is proportional to its depth.

2nd. The pressure is the same on all points of the same horizontal layer.

3rd. At the same depth, in different liquids, the pressure is proportional to the density of the liquid.

4th. In the same liquid, the pressure on any layer is independent of the form of the vessel, and only depends on the depth of that layer.

Three of these laws may be considered as self-evident; the proof of the fourth will be seen when we come to the con. num-sideration of the pressure on the bottom of vessels.

Vertical Pressure Upwards.-The downward pressure of the

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moves, is fixed to a hollow globe on which are placed a ber of small cylindric pipes, all perpendicular to the surface. The globe and the cylinder being filled with water, if the pis-upper layers of a liquid upon those which are below them, ton be pushed inwards the water will spout through all the orifices or pipes, and not through that only which is opposite to the piston. The reason why the principle of equality of pressure, or, as it has been elegantly termed, the Quaquaversal Pressure, cannot be perfectly proved, is that in our experiments we cannot take away weight from the liquids, nor friction from the pistons which communicate pressure to them.

Direction of the Surface of Liquids.-When a liquid is acted on by the force of gravity only, its surface always tends to take a direction perpendicular to the direction of that force. Thus, suppose that the surface of a liquid, as water, takes for an instant the direction B A, fig. 22, inclined to the horizon, the Fig. 22.

produces in the latter a reaction which is equal and contrary, in consequence of the principle of the communication of pressure in all directions. This upward pressure is denominated the resistance of liquids. It is very sensible when we push our hand into a liquid, especially if it be one of great density, such as mercury.

Fig. 23.

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B

Be in kavity P on any particle m of this surface having

To prove this fact by experiment, we employ a glass tube open at both ends, fig. 23. To the lower end of this tube is applied a disk of glass B, which serves as a stopper, and which is supported in its position by means of a thread & which is fastened to it. This apparatus being immersed in a glass vessel nearly full of water, the hand is removed from the thread and the disk is left free. This disk then remains as a stopper applied to the tube, indicating that it is supported by the upward pressure of the water, which is greater than the downward pressure of its weight. Now, if water be slowly poured into the tube, the disk will continue to support this water until the level of the water within the tube is nearly the same as that without, when the disk will fall to the bottom of the vessel. This experiment proves that the downward pressure on the disk is equal to a column of water having for its base the interior section of the tube, and for its height the distance of the disk from the upper surface of the water in which the tube is immersed. Hence, the resistance or upward pressure of liquids, as well as their downward pressure, is proportional to their depth.

Pressure on the Bottom of Vessels.-The pressure of a liquid on the bottom of the vessel which contains it, is regulated by the same laws as the pressure on any layer of that liquid; that is, it depends only on the density of the liquid and on its depth, and not on the form of the vessel. That the pressure on the bottom of vessels is independent of their form is proved by the following experiment, the apparatus for which was invented by M. de Haldat.

This apparatus is composed of a bent tube A CD, fig. 24, on

As to the bottom

the quantity of liquid which it contains of the vessel, it is evidently the same in the two cases, that is, the surface of the mercury in the tube A C.

From this law, it is evident that by means of a very small quantity of water very considerable pressures may be obtained. For this purpose, we have only to fix in the side of a closed vessel full of water a tube of very small diameter and of great height; this tube being filled with water, the pressure communicated to the side of the vessel is equal to the weight of the column of water which has this side for its base, and whose height is equal to the height of the tube, Thus the pressure of the water on the side of the vessel may be indefinitely increased. In this manner, a narrow pipe of water of the height of 33 feet has burst a strong and well-constructed cask.

exists at the bottom of the sea may be determined. It is On the principle just proved, the pressure of water which known, and will soon be proved, that the pressure of the atmosphere is equivalent to that of a column of water of 33 feet. Now navigators have often observed that the sounding lead does not reach the bottom of the sea at a depth of about 13,200 feet. There is therefore a pressure equal to 400 times that of the atmosphere at the bottom of a sea of the depth of 2 miles.

Lateral Pressure of Liquids.-The pressure which arises from gravity in the mass of a liquid is communicated in all directions according to the quaquaversal principle; hence, it follows that the pressures which take place perpendicularly to the vertical sides of vessels are included in the laws of vertical

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which, at A, two vessels м and can be screwed in succession, of the same depth, but of different form and capacity, the first being conical and the second cylindrical. The experiment is made by pouring mercury into the tube A c, until its level nearly reaches the cock A. The vessel м is then screwed on the tube and filled with water; the water by its weight forces the mercury back and causes it to rise in the tube at c H, and its level is marked by means of a slide H, which moves along the part of the tube o D. The level of the water in the vessel M is marked by means of a moveable rod placed anove it. These levels being noted, the vessel м is emptied by the cock at A; it is then unscrewed, and replaced by the vessel P. Now, on pouring water into this vessel, the mercury which had resumed its original level in the tube at A, is again raised in the tube at c; and as soon as the water reaches the same level in the vessel P, which it had in the vessel M (which is preserved by the position of the rod above it), the mercury takes exactly the same level in the tube at H, as it did before, this being indicated by the slide H. This pressure is therefore independent of the shape of the vessel, and consequently of

pressure. It has been proved both by analysis and by experi ment, that the pressure on a given side of a vessel is equal to the weight of a column of water which has that side for its base, and for its height the vertical distance of its centre of gravity from the surface of the water. As to the point of application of this pressure, it is always a little below the centre of gravity. This point is in fact called the centre of pressure; and its position is determined by calculations of which the following are some results: Ist. The centre of pressure of a rectangular side, of which the upper edge is level with the water, is situated downwards from that edge at twothirds of the straight line which joins the middle of its horizontal edges. 2nd. The centre of pressure of a triangular side of which the base is level with the upper surface of the water, is in the middle of the straight line which joins the vertex of the triangle with the middle of the base. 3rd. The centre of pressure of a triangle whose vertex is at the level of the water, and base horizontal, is at the distance of three-fourths of the straight line joining the vertex and the middle of the base from that vertex.

The Hydraulic Tourniquet.-When a liquid is in equilibrium in a vessel, it produces on the opposite sides along each horizontal layer pressures equal and contrary in pairs, which counteract each other, so that the existence of these pressures is not manifest; they are, however, proved by the Hydraulic Tourniquet. This apparatus is composed of a glass vessel, fig. 25, which, resting on a pivot, revolves freely round a vertical Fig. 25.

principle of Pascal, the upward pressure of the liquid column, whose section is HEFG, on the annular side of which PGFR is a section, is equal to the weight of a column of water which would fill the space of which OPG HEFRI is a section. The effective pressure of the liquid on the body supporting the Fig. 26.

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base, is therefore the weight of the volume of water which fills the space whose section is o M N I, diminished by that of the water which would be contained in the space whose section is OPGHEFRI, that is, in fact, the weight of water actually contained in the given vessel.

If the vessel has the same diameter throughout, the water presses with the same force both on the bottom and on the supporting body; if the vessel has a greater diameter at the top than at the bottom, the pressure on the bottom is less than on the supporting body.

LESSONS IN BOOKKEEPING.-No. VII.

HOME TRADE.

(Continued from page 341, Vol. III.)

axis. On this vessel, at its lower end, is fixed, perpendicular to its axis, a copper tube bent horizontally at its two ends and in opposite directions, the bottom of the vessel being fixed in the middle of the tube. If the apparatus be filled with water, and the tube quite closed at both ends, the interior pressures on the sides of the tube counteract each other, and no motion ensues. But if the tube be open at both ends, the liquid escapes, and then the pressure no longer acts on the sides at the orifices B, but only on the opposite sides at A, as seen in the sketch on the right of the figure. The pressure which takes place at A being no longer balanced by the pressure on the opposite point at B, acts upon the tube and on the whole vessel so as to produce a motion of rotation in the direction of the arrow, in the sketch to the right of the figure; this motion being more or less rapid in proportion to the height of the liquid in the vessel, and to the section of the orifices from which the water issues. The motion produced in this appara-workmen proceeding to prepare the mortar and stones or tus, is similar to that exhibited in the machine known by the name of Barker's mill. The lateral pressure of water is applied in a useful and important manner in the construction of the hydraulic machines called Wheels of Reaction.

WHEN you see in a city, such as London, a space of ground dug up to a certain depth, and surrounded by a hoard, that is, an enclosure formed of a collection of boards fastened to posts driven into the ground, you then begin to think that a building is about to commence, that a superstructure is about to be raised, and that its foundation is in the process of preparation. You are still more convinced of the fact, when you see cartloads of stone, brick, and lime deposited within the hoard, and

Hydrostatic Paradox.-We have already seen that the pres-structure which shall constitute a model for your guidance in sure on the bottom of a vessel full of liquid depends neither on the form of the vessel nor on the quantity of the liquid, but only on the height of the level of the liquid above the bottom. Now, the pressure on the bottom of the vessel must not be confounded with that of the vessel itself on the body which supports it. The latter is always equal to the whole weight of the vessel and of the liquid which it contains; while the former may be greater than this, less than this, or equal to it, according to the form of the vessel. This curious fact is commonly known under the name of the Hydrostatic Paradox, because that, at first sight, it seems to be paradoxical, that is, contrary to receive notions.

To explain this paradox, let FPN, fig. 26, be the vertical section of a vessel formed of two cylindrical parts in one piece, but of unequal diameter. Let it be filled with water; then as the horizontal pressures balance each other on all its sides, these may be left out of consideration. The vertical pressure upon the bottom мN, is equal to the weight of a column of the liquid which has this bottom for its base, and the height o M for its altitude; that is, this pressure is the same as if the vessel had м N10 for its vertical section, and was completely filled with water. This pressure is not wholly communicated to the body which supports the vessel; for according to the

bricks for the foundation. So it is in the system of Book-.
keeping by Double Entry, which we are about to lay before
you. We must begin with a series of Transactions in Business,
which are arranged in the exact order of their occurrence, as
the materials to be employed in forming a system or super-
keeping the books of any Mercantile house in which you may
hereafter be engaged. We have selected the supposed trans-
actions of a particular branch of Home Trade, namely, that of a
Cotton Merchant, as one well adapted, from its simplicity and
generality, to exemplify the principles which we have ex-
plained in former Lessons.
transactions in order from January, when we suppose the
We have arranged these
business to be commenced, till June, when we suppose a
Balance to be struck, and the Merchant's Real Worth ascer-
tained. These six months' transactions in the Cotton trade
are interspersed with various Banking, Bill, and Cash trans-
actions, such as might be supposed to occur in the business
of a Cotton Merchant resident in the metropolis; and the
whole is afterwards entered in the various subsidiary books which
belong to such a business; then into the Journal; and, lastly,
into the Ledger. The General Balance is. then taken, and the
difference between the Assets and Liabilities, or the Real
Worth of the Merchant, is ascertained from the Ledger alone.
The remarks which it will be necessary to make concerning
the method of Balancing the Books, a process equivalent to the
taking of stock among tradesmen and others, who only use
Single Entry, we must postpone until we have shown how to
make up the Subsidiary Books of our system.

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