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M. Muller has observed that, with a membraneous tongue, the sound is produced whether we blow or draw the air through it with the mouth. But in the latter case, the sound is usually lower by a semitone or a full tone. An increase in the force of blowing out or drawing in the air raises the tone a little. Up to a certain limit, the breadth has little influence in raising the sound; but the sound is lost when the slit is too large. In membraneous tongues, as well as in tense cords, the tone is raised when the tension is increased. If we fix the tongue in the middle and blow on one-half of it, we obtain the octave of the fundamental sound produced by the entire tongue. Membraneous tongues are subject to the same laws as tense cords, while rigid tongues follow those of elastic lamina. M. Muller has particularly experimented on the tongues which are formed of two elastic membranes with a slit between them. He has proved that if two meinbranes are equally stretched, they emit a lower sound than the fundamental sound separately emitted by each. When a pipe was fitted to the tongue, the sound became lower still, and blowing through a porte-vent produced the same effect. Membraneous tongues have not hitherto been applied in music; but it is to this kind of apparatus that we must refer the construction of the human voice and the singing of birds.

When the lips are contracted by the muscles, they can act like membraneous tongues. The buccal cavity and the respiratory organs represent the porte-vent. The lips act in the same manner in blowing the horn, the trumpet, and the trombone; for it is not enough merely to blow into these instruments, but the lips also must be put into a state of vibration like membraneous tongues. It is for this reason that mouth-pieces are used of a diameter smaller in proportion as the sound is to be raised higher, and so that the lips may be contracted or widened according as the sound is to be elevated or lowered.

The Organ of the Voice.-The voice is a sound produced in a particular organ, called the larynx, at the moment when it is traversed by the air breathed from the lungs. The larynx is a wide and short pipe placed between the back of the mouth and the trachea, or canal which conveys the air to the lungs. A mucous membrane lines the interior of the larynx and passes over two ligaments which have between them a triangular opening with the base behind and the vertex in front. These ligaments are the lower vocal cords. Above them the larynx enlarges, then diminishes, and the mucous membrane covers two new but weaker ligaments, which are called the upper vocal cords, having between them an opening similar to the former. The space between each vocal cord, the lower and the upper, to the right and to the left, presents two cavities which are called the ventricles of the larynx. The triangular space comprised between the vocal cords, right and left, is called the glottis. The edges of the openings are called the lips of the glottis, and their distance from each other varies with the action of certain muscles. Above the glottis there is a kind of fibro-cartilaginous moveable valve called the epiglottis; it is intended to prevent, in the action of swallowing, the entrance into the larynx of food, solid or liquid, which, by its stoppage in the wind-pipe, would occasion suffocation. Moreover, the apparatus of the voice is completed by the buccal cavity, the upper part of the pharynx, or opening of the gullet and windpipe, and the nasal apertures. In order that the sound of the voice may be produced, two conditions are necessary: 1st, that the air contained in the lungs may be expelled by expiration; 2nd, that the muscles of the glottis may exert, under the power of the will, a tension properly adapted to the vocal cords. We know, indeed, that the sound of the voice is not produced at every expiration; and when the nerves which belong to the muscles of the larynx are cut, complete dumbness takes place. What proves that the sound of the voice is produced chiefly in the larynx, is, that when the trachea has been opened, the air breathed out is carried off through the artificial opening without traversing the larynx, and no sound can be produced; on the other hand, the voice resumes its proper character when the opening is closed. Besides, the voice remains, if an opening be made above the glottis, so that the air is breathed out through the larynx.

that effect this. In fact, all the other parts of the larynx, even
the upper vocal cords and epiglottis, may be destroyed, with-
out destroying the voice; but it is entirely lost, if the lower
vocal cords are destroyed.

The production of the sound of the voice has received much
attention from natural philosophers and physiologists. This
organ has in its turn been compared to a flute, to a stringed
instrument, to a tongued instrument, and to the catcal of bird-
catchers. The essential difference between these various
opinions is, whether the air alone is put into vibration by
striking against the lips of the glottis, in the same manner as
in the instruments having a mouth-piece; or, whether the
vocal cords themselves, which are struck by the air breathed
out of the lungs, are the first to vibrate, and thus become the
producers of the sound. From the experiments on the caout-
chouc membranes already described, M. Muller concludes
that it is the membraneous parts of the larynx which vibrate,
and that the organ of the voice may be compared to a double
membraneous tongue. This hypothesis appears to be the most
satisfactory; but, after all, the organ of the voice is of a nature
entirely its own, and cannot be compared in an absolute man-
ner with any known instrument. We may, however, draw a
limit on this point, by considering it as a wind-instrument in
which the lungs represent the blowing machine; the trachea
the porte-vent; and the mouth the box or apparatus for
strengthening and modifying the sound, in a manner similar to
that of the horn with tongued pipes. In the articulated voice,
or uttered word, the tongue, teeth, and lips play an important
part in the pronunciation of the vowels and consonants.
The Organ of Hearing.-The ear is the organ by means of
which we are made sensible of the undulations of sonorous
bodies, and these are transmitted by the external air to the
acoustic nerve. The cartilaginous external car acts like the
funnel of a hearing trumpet, of which the tube commences at
the acoustic or auditory nerve, and is hollowed out at the os tem-
poralis. It is by this canal that the sonorous waves are intro-
duced, and made to strike and put into vibration an elastic
membrane stretched at the bottom of the canal, called the
tympanum or drum. Beyond this membrane there is a cavity,
called the middle ear or cavity of the tympanum, which is filled
with air received from the back part of the mouth by a canal
called the Eustachian tube or horn. Behind this cavity, and
opposite to the membrana tympani, there is a membrane of the
same kind which closes two apertures called the fenestra ovalis
and the fenestra rotunda. These two membranes are connected
by a chain of small bones called the malleus, the incus, the os
orbiculare, and the stapes, and put in action by two muscles.
The vibrations of the membrana tympani are transmitted to
the membrane of the fenestra ovalis by means of this osseous
chain, from the air in the cavity of the tympanum, and from
the bony sides of this cavity. The fenestra ovalis and the
fenestra rotunda put this cavity in communication with the
vestibulum, which is placed at the end of the system of canals
called the cochlea, and the three semicircular canals, which together
form the labyrinth or internal ear. These canals contain a fluid
in which the threads of the auditory nerve are immersed. The
vibrations of the membrane of the fenestræ are transmitted to
this fluid and to the auditory nerve; and this nerve, by trans-
mitting its impressions to the brain, realises the condition
nece ssary to the sensation of hearing, see fig. 155.

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It has also been determined in what part of the larynx the A, Fannel of the External Ear-B, Meatus Auditorius-C, the Lobe of the

sound of the voice is produced. The experiments of MM. Bichat and Magendie prove that it is the lower vocal cords

External Ear-D, the Cavity of the Tympanum-E, the Eustachian
Tube-E, the Cochlea-G, the Acoustic Nerve-H, the Vestibulum and
Semicircular Canals-1, the Membrana Tympani,

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LESSONS IN CHEMISTRY.-No. XXVII. The Metal Lead.-The physical characteristics of this very useful metal are so well known, that they scarcely require description. Soft, blueish white, possessing considerable specific gravity, very fusible, laminable, ductile, easily tarnishing on exposure to air,-lead, when obtained free from combination, could scarcely be confounded with any other metal. Not only is lead very plentifully distributed throughout nature, but it is a very useful metal, as the slightest reflection will demonstrate to the student. Its combinations, however, are for the most part poisonous, the amount of their power being dependent on their degree of solubility; and as lead is employed for thousands of purposes involving intimate contact with articles of food and drink, it behoves us to be able to appreciate the conditions under which this metal, so useful a servant, may become an

insidious enemy.

Chemical Qualities of Lead Combinations.-Combinations of this metal, as of every other, admit of classing into the soluble and the insoluble. For the purposes of our experiments we shall require a soluble solution, and none is better for our purposes than a solution of acetate of lead, commonly called "sugar of lead." It consists of protoxide of lead united with acetic acid, Take about as much as will lie heaped upon a fourpenny piece of crystallised sugar of lead, and dissolve it in about a wine-glass full of common water; if pump or well-water, all the better. Try to dissolve it, I should have said; because, as the operator will find, perfect solution cannot be effected, but a white powder will remain. So far, then, as concerns the solution we were desirous of making, our operation is a failure. I meant it to be a failure, in order to demonstrate a fact. The white appearance developed is, however, not without its own significance, and we shall revert to it by-and-by; meantime preserve the whitened liquor in a properly-labelled corked bottle. Repeating now the experiment with the substitution of pure distilled water for impure or common water, a solution of absolute transparency will result, if the water employed be totally free from impurity; gradually, however, it will be found that mere contact with atmospheric air gives rise to a certain turbidity, and this for a reason we shall discover presently.

Having prepared our solution, let us now deal with it analytically. Let the reader assume it to be unknown; let him, for the purpose of argument, call it x. What is the x? Such is the question we require to solve.

By this time the student will know intuitively, so to speak, the series of questions we have to demand of our unknown x. Is it a metal? Yes or no. If a metal, what class of metal? what section of the class? and lastly, what metal?

boiling, it will be found to dissolve completely. In other words, the white substance obtained by the addition of chloride of sodium to acetate of lead is the chloride of lead, which is so far from being totally insoluble in water (even cold), that we were obliged to add alcohol in order to insure its absolute precipitation; and is so perfectly soluble in hot water that we have been enabled to convert the former white powder into a colourless solution. This precipitate, moreover, is neither whitened nor turned black by the agency of ammonia. Let us now draw these facts into one focus and appreciate their significance. In the first place, we have already seen that there only exist two metals the chlorides of which possess the slightest claim to the quality of insolubility: of these the protochloride of mercury (calomel) and the chloride of silver may be regarded as absolutely insoluble (in water); the third, which is chloride of lead, is not absolutely insoluble. Clearly, then, it is chloride of lead we are dealing with, and consequently the metal whose solution we are investigating must be lead. The action of ammonia still further demonstrates that it can neither be chloride of silver nor of mercury. However, the chemist would scarcely think it safe, in any instance, to rely implicitly on the indications of one line of testing. He would scarcely then be warranted in allowing our unknown x to escape without further questioning. Effect of Sulphuric Acid and soluble Sulphates on Salts of Lead.Let me premise, in reference to these tests, that the sulphuric acid to be employed as a test in this instance should be for convenience diluted, the dilution being in the ratio of about one of acid and nineteen of water (by measure). As to the soluble sulphates, the experimentalist may either employ sulphate of soda, much used in veterinary practice under the name of "Glauber's salt," or else sulphate of magnesia, better known as "Epsom salts." Taking a little of the solution of x, add to it a portion of dilute sulphuric acid, or any soluble sulphate. Remark the heavy white precipitate which deposits. Remark, too, how insoluble this precipitate is in water-even hot: for if a portion be boiled in pure water, the clear liquid decanted, and tested with hydrosulphuric acid, not the slightest blackening results; an evidence so palpable as to require no comment. Remark, too, that this same white precipitate is scarcely soluble, if soluble at all, in nitric acid, even though boiling.

All the facts of this line of demonstration prove that we are dealing with sulphate of lead. Only one sulphate besides it has an equal amount of insolubility; this one is the sulphate of baryta, which, however, is generated out of a solution neither precipitable by chlorides nor by hydrosulphuric acid. Before leaving the sulphate of lead, let the experimentalist satisfy himself that a precipitate identical in every respect may be generated by the substitution of a soluble sulphate for sulphuric acid.

With these facts before him-namely, with the double evidence supplied by the agency of chlorides, on the one hand, and sulphuric acid and sulphates on the other, the operator need not entertain a doubt as to the name of the metal x. It must be lead. Nevertheless I shall mention further tests presently; not that they are required so far as our present exami nation goes, but that they might be required under other circumlet us well contemplate some practical applications which admit of being made, of chemical reactions already brought before us. All soluble lead compounds are poisonous, as I have already remarked; and of course all absolutely insoluble ones are innocuous. Supposing, then, a naturally fatal dose of acetate of lead, or any other soluble salt of that metal, swallowed-what would be the antidote to the same? Our aim would not be to convert the soluble salt into the chloride, certainly; because the latter is scarcely to be cailed insoluble. We should try to convert it into the absolutely insoluble sulphate: but how?

I need scarcely state that you will begin your testing operation by the employment of hydrosulphuric acid in aqueous solution. It yields a black precipitate, thereby teaching us that the solution we have to deal with not only contains a metal, but a metal of the calsigenous class; teaches us, moreover, that the metal is neither iron, manganese, uranium, cobalt, or nickel, all of which require hydrosulphate of ammonia to effect their precipitation: teaches us that the metal is neither zinc, nor arsenic, nor antimony, cad-stances. Meantime, before proceeding to these further tests, mium, or tin in per-combination; since, were it either of these, the precipitate could not be black. Gradually, then, we have narrowed the list of bodies to which our a might belong. The analyst might now, in the ordinary course of testing, employ an aqueous solution of ferrocyanide of potassium (prussiate of potash) as a test; under which circumstances he would obtain a whitish precipitate-the teaching conveyed by which would be still less than that already imparted by the hydrosulphuric acid. The operator would now have recourse to "random tests;" likely enough he would at once have recourse to a soluble chloride, say chloride of sodium, or common salt. Supposing a solution of this substance employed-the stronger the better, saturated by preference-he would most likely obtain from a solution of acetate of lead of the strength described, a white precipitate. I say most likely, because in proportion as the temperature of the lead-containing solution is higher, so is the tendency less of the white precipitate to fall. Its precipitation, however, may be assured by adding a certain amount of alcohol (rectified spirit of wine).

On collecting a little of this white precipitate (say a few grains), placing it in a little flask, adding pure water, and

To administer sulphuric acid pure would be out of the question: to administer dilute sulphuric acid would be highly dangerous; but the young chemist will not fail to see that a soluble sulphate (Epsom salts) might be given with advantage, even though administered in excess. Having, then, once established the fact of poisoning by an over-dose of lead salt, administer solution of Epsom salt copiously. This is the antidote. In our next lesson we shall resume the consideration of the tests for lead solutions, and perhaps discuss the peculiarities of the metal when operated upon in the dry way.

4th.

LESSONS IN BOOKKEEPING.-No. XIV.

(Continued from page 230, Vol. IV.)

FOREIGN TRADE.

Effected by Andrew Lloyd, an insurance on
7hhds. of Sugar, valued at £25 per hhd., from
Berbice to London, at 3 per cent., the amount of
premium being
Policy duty

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4th.

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Effected for account of Nathan Herschell, Barba-
does, the foregoing Insurance
Premium and Policy on £175
Commission on do., at per cent.

Victoria

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HAVING allowed our students time to study the principles and
practice of Bookkeeping as applicable to the transactions of
Home Trade, we now proceed to lay before them a series of
transactions in Foreign Trade; and afterwards to show them
how to enter these transactions into the proper books, as we
have done in our preceding Lessons in reference to Home
Trade. The following Memoranda of Transactions are to be
entered in the same manner as before; 1st, All Receipts and
Payments of Cash in the Cash Book. Here, however, the
transactions with the Bank are to be entered along with the
Cash transactions in business; but they are not recorded in
the Memoranda, because they would take up a quantity of Received of David Anderson for freight per Ship
unnecessary space, and the student can easily judge for him-
self how much money must be drawn from the Bank each day
for the Payments, or how much should be lodged in the Bank
from the Receipts. For this purpose, of course, he will make
the proper entries in the separate columns appointed_for_the
Bank transactions as shown in the Cash Book under the Head
of Home Trade. This process renders it unnecessary for the
Merchant to keep a separate Bank account or Bank Book
and it shows by the balances at the end of the month, or of
any other period when they are taken, how the Bank and
Business Cash transactions operate as a check on each other,
the difference between these balances being always the amount
of cash in hand.

2nd, All Drafts and Remittances of Bills are entered in

:

8th.

Effected by Andrew Lloyd, an Insurance on £700,
on 20 tierces of coffee, valued at £35 per tierce,
from Berbice to London, at 2 per cent. pre-
mium

Policy

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the foregoing Insurance
Premium and Policy on £700
Commission on do., at per cent

12th.

the Bills Receivable Book, and all Acceptances of Bills in
the Bills Payable Book. In these two books, the columns for
the various particulars relating to the Bills are more numerous
than those shown in the Bill Books under the head of Home
Trade; the student will, of course, be directed by the titles of
these columns to insert every particular in its proper place. Paid Bill No. 101, Robert Simpson
3rd, The particulars of all the other transactions relating to
the Foreign Trade are entered in the Day Book; but many of
these particulars are copied from other Books usually kept in
a Merchant's Counting House; viz. the Invoice Book, the
Account Sales Book, the Account Current Boo the Insurance
Book, etc.

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August 1st.

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Purchased Goods of the following persons,
Of Samuel Morley, 9 bales tow Osnaburgs £236 5
Tuelon and Co., 3 cases of hats
32 2

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LESSONS IN CHEMISTRY.-No. XXVII. The Metal Lead.-The physical characteristics of this very useful metal are so well known, that they scarcely require description. Soft, blueish white, possessing considerable specific gravity, very fusible, laminable, ductile, easily tarnishing on exposure to air,-lead, when obtained free from combination, could scarcely be confounded with any other metal. Not only is lead very plentifully distributed throughout nature, but it is a very useful metal, as the slightest reflection will demonstrate to the student. Its combinations, however, are for the most part poisonous, the amount of their power being dependent on their degree of solubility; and as lead is employed for thousands of purposes involving intimate contact with articles of food and drink, it behoves us to be able to appreciate the conditions under which this metal, so useful a servant, may become an

insidious enemy.

Chemical Qualities of Lead Combinations.-Combinations of this metal, as of every other, admit of classing into the soluble and the insoluble. For the purposes of our experiments we shall require a soluble solution, and none is better for our purposes than a solution of acetate of lead, commonly called "sugar of lead." It consists of protoxide of lead united with acetic acid. Take about as much as will lie heaped upon a fourpenny piece of crystallised sugar of lead, and dissolve it in about a wine-glass full of common water; if pump or well-water, all the better. Try to dissolve it, I should have said; because, as the operator will find, perfect solution cannot be effected, but a white powder will remain. So far, then, as concerns the solution we were desirous of making, our operation is a failure. I meant it to be a failure, in order to demonstrate a fact. The white appearance developed is, however, not without its own significance, and we shall revert to it by-and-by; meantime preserve the whitened liquor in a properly-labelled corked bottle. Repeating now the experiment with the substitution of pure distilled water for impure or common water, a solution of ab. solute transparency will result, if the water employed be totally free from impurity; gradually, however, it will be found that mere contact with atmospheric air gives rise to a certain turbidity, and this for a reason we shall discover presently.

Having prepared our solution, let us now deal with it analytically. Let the reader assume it to be unknown; let him, for the purpose of argument, call it x. What is the x? Such is the question we require to solve.

By this time the student will know intuitively, so to speak, the series of questions we have to demand of our unknown x. Is it a metal? Yes or no. If a metal, what class of metal? what section of the class? and lastly, what metal?

I need scarcely state that you will begin your testing operation by the employment of hydrosulphuric acid in aqueous solution. It yields a black precipitate, thereby teaching us that the solution we have to deal with not only contains a metal, but a metal of the calcigenous class; teaches us, moreover, that the metal is neither iron, manganese, uranium, cobalt, or nickel, all of which require hydrosulphate of ammonia to effect their precipitation: teaches us that the metal is neither zinc, nor arsenic, nor antimony, cadmium, or tin in per-combination; since, were it either of these, the precipitate could not be black. Gradually, then, we have narrowed the list of bodies to which our x might belong. The analyst might now, in the ordinary course of testing, employ an aqueous solution of ferrocyanide of potassium (prussiate of potash) as a test; under which circumstances he would obtain a whitish precipitate-the teaching conveyed by which would be still less than that already imparted by the hydrosulphuric acid. The operator would now have recourse to "random tests;" likely enough he would at once have recourse to a soluble chloride, say chloride of sodium, or common salt. Supposing a solution of this substance employed-the stronger the better, saturated by preference-he would most likely obtain from a solution of acetate of lead of the strength described, a white precipitate. I say most likely, because in proportion as the temperature of the lead-containing solution is higher, so is the tendency less of the white precipitate to fall. Its precipitation, however, may be assured by adding a certain amount of alcohol (rectified spirit of wine).

On collecting a little of this white precipitate (say a few grains), placing it in a little flask, adding pure water, and

boiling, it will be found to dissolve completely. In other words, the white substance obtained by the addition of chloride of sodium to acetate of lead is the chloride of lead, which is so far from being totally insoluble in water (even cold), that we were obliged to add alcohol in order to insure its absolute precipitation; and is so perfectly soluble in hot water that we have been enabled to convert the former white powder into a colourless solution. This precipitate, moreover, is neither whitened nor turned black by the agency of ammonia. Let us now draw these facts into one focus and appreciate their significance. In the first place, we have already seen that there only exist two metals the chlorides of which possess the slightest claim to the quality of insolubility of these the protochloride of mercury (calomel) and the chloride of silver may be regarded as abso lutely insoluble (in water); the third, which is chloride of lead, is not absolutely insoluble. Clearly, then, it is chloride of lead we are dealing with, and consequently the metal whose solution we are investigating must be lead. The action of ammonia still further demonstrates that it can neither be chloride of silver nor of mercury. However, the chemist would scarcely think it safe, in any instance, to rely implicitly on the indications of one line of testing. He would scarcely then be warranted in allowing our unknown x to escape without further questioning.

:

Effect of Sulphuric Acid and soluble Sulphates on Salts of Lead.Let me premise, in reference to these tests, that the sulphuric acid to be employed as a test in this instance should be for convenience diluted, the dilution being in the ratio of about one of acid and nineteen of water (by measure). As to the soluble sulphates, the experimentalist may either employ sulphate of soda, much used in veterinary practice under the name of "Glauber's salt," or else sulphate of magnesia, better known as "Epsom salts." Taking a little of the solution of x, add to it a portion of dilute sulphuric acid, or any soluble sulphate. Remark the heavy white precipitate which deposits. Remark, too, how insoluble this precipitate is in water-even hot: for if a portion be boiled in pure water, the clear liquid decanted, and tested with hydrosulphuric acid, not the slightest blackening results; an evidence so palpable as to require no comment. Remark, too, that this same white precipitate is scarcely soluble, if soluble at all, in nitric acid, even though boiling.

All the facts of this line of demonstration prove that we are dealing with sulphate of lead. Only one sulphate besides it has an equal amount of insolubility; this one is the sulphate of baryta, which, however, is generated out of a solution neither precipitable by chlorides nor by hydrosulphuric acid. Before leaving the sulphate of lead, let the experimentalist satisfy himself that a precipitate identical in every respect may be generated by the substitution of a soluble sulphate for sulphuric acid.

With these facts before him-namely, with the double evidence supplied by the agency of chlorides, on the one hand, and sulphuric acid and sulphates on the other, the operator need not entertain a doubt as to the name of the metal x. It must be lead. Nevertheless I shall mention further tests presently; not that they are required so far as our present examination goes, but that they might be required under other circumstances. Meantime, before proceeding to these further tests, let us well contemplate some practical applications which admit of being made, of chemical reactions already brought before us. All soluble lead compounds are poisonous, as I have already remarked; and of course all absolutely insoluble ones are innocuous. Supposing, then, a naturally fatal dose of acetate of lead, or any other soluble salt of that metal, swallowed-what would be the antidote to the same? Our aim would not be to convert the soluble salt into the chloride, certainly; because the latter is scarcely to be cailed insoluble. We should try to convert it into the absolutely insoluble sulphate: but how?

To administer sulphuric acid pure would be out of the question: to administer dilute sulphuric acid would be highly dangerous; but the young chemist will not fail to see that a soluble sulphate (Epsom salts) might be given with advantage, even though administered in excess. Having, then, once established the fact of poisoning by an over-dose of lead salt, administer solution of Epsom salt copiously. This is the antidote. In our next lesson we shall resume the consideration of the tests for lead solutions, and perhaps discuss the peculiarities of the metal when operated upon in the dry way.

LESSONS IN BOOKKEEPING.-No. XIV.

(Continued from page 230, Vol. IV.)

FOREIGN TRADE.

4th.

Effected by Andrew Lloyd, an insurance on
7hhds. of Sugar, valued at £25 per hhd., from
Berbice to London, at 3 per cent., the amount of
premium being
Policy duty

...

4th.

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Effected for account of Nathan Herschell, Barba-
does, the foregoing Insurance
Premium and Policy on £175
Commission on do., at per cent.

Victoria

6th,

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HAVING allowed our students time to study the principles and
practice of Bookkeeping as applicable to the transactions of
Home Trade, we now proceed to lay before them a series of
transactions in Foreign Trade; and afterwards to show them
how to enter these transactions into the proper books, as we
have done in our preceding Lessons in reference to Home
Trade. The following Memoranda of Transactions are to be
entered in the same manner as before; 1st, All Receipts and
Payments of Cash in the Cash Book. Here, however, the
transactions with the Bank are to be entered along with the
Cash transactions in business; but they are not recorded in
the Memoranda, because they would take up a quantity of Received of David Anderson for freight per Ship
unnecessary space, and the student can easily judge for him-
self how much money must be drawn from the Bank each day
for the Payments, or how much should be lodged in the Bank
from the Receipts. For this purpose, of course, he will make
the proper entries in the separate columns appointed for the
Bank transactions as shown in the Cash Book under the Head
of Home Trade. This process renders it unnecessary for the
Merchant to keep a separate Bank account or Bank Book
and it shows by the balances at the end of the month, or of
any other period when they are taken, how the Bank and
Business Cash transactions operate as a check on each other,
the difference between these balances being always the amount
of cash in hand.

2nd, All Drafts and Remittances of Bills are entered in

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the Bills Receivable Book, and all Acceptances of Bills in
the Bills Payable Book. In these two books, the columns for
the various particulars relating to the Bills are more numerous
than those shown in the Bill Books under the head of Home
Trade; the student will, of course, be directed by the titles of
these columns to insert every particular in its proper place. Paid Bill No. 101, Robert Simpson
3rd, The particulars of all the other transactions relating to
the Foreign Trade are entered in the Day Book; but many of
these particulars are copied from other Books usually kept in
a Merchant's Counting House; viz. the Invoice Book, the
Account Sales Book, the Account Current Boo the Insurance
Book, etc.

MEMORANDA OF TRANSACTIONS.
July 1st, 1854.

Inventory of the Assets and Liabilities of the House of
White, Smith and Company, Merchants, London, as per
Balance Sheet of Ledger B.

18th.

£6 13 0

£175 3 0

£17 10 0 1 16 9

£19 6 9

£19 6 9 3 10 0

£22 16 9

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ASSETS.

2nd.

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