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M. Muller has observed that, woh a membraneous tongue, that effect this. In fact, all the other parts of the larynx, even the sound is produced whether we blow or draw the air the upper vocal cords and epiglottis, may be destroyed, withthrough it with the mouth. But in the latter case, the sound out destroying the voice; but it is entirely lost, if the lower is usually lower by a semitone or a full tone. An increase in vocal cords are destroyed. the force of blowing out or drawing in the air raises the tone The production of the sound of the voice has received much a little. Up to a certain limit, the breadth has little influence attention from natural philosophers and physiologists. This in raising the sound; but the sound is lost when the slit is organ has in its turn been compared to a flute, to a stringed too large. In membraneous tongues, as well as in tense cords, instrument, to a tongued instrument, and to the catcal of birdthe tone is raised when the tension is increased. If we fix catchers. The essential difference between these various the tongue in the middle and blow on one-half of it, we obtirin opinions is, whether the air alone is put into vibration by the octave of the fundamental sound produced by the entire striking against the lips of the glottis, in the same minner as tongue. Membraneous tongues are subject to the same laws as in the instruments having a mouth-piece; or, whether the tense cords, while rigid tongues follow those of elastic laminæ. vocal cords themselves, which are struck by the air breathed

M. Muller has particularly experimented on the tongues out of the lungs, are the first to vibrate, and thus become the which are formed of two elastic membranes with a slit producers of the sound. From the experiments on the caoutbetween them. He has proved that if two membranes are chouc membranes already described, M. Muller concludes equally stretched, they emit a lower sound than the funda- that it is the membraneous parts of the larynx which vibrate, mental sound separately emitted by each. When a pipe was and that the organ of the voice may be compared to a double fitted to the tongue, the sound became lower still, and blowing membraneous tongue. This hypothesis appears to be the most through a porte-vent produced the same effect. Membraneous satisfactory; but, after all, the organ of the voice is of a nature tongues have not hitherto been applied in music; but it is to entirely its own, and cannot be compared in an absolute manthis kind of apparatus that we must refer the construction of ner with any known instrument. We may, however, draw a the human voice and the singing of birds.

limit on this point, by considering it as a wind-instrument in When the lips are contracted by the muscles, they can act which the lungs represent the blowing machine ; the trachea like membraneous tongues. The buccal cavity and the respi- the porte-vent; and the mouth the box or apparatus for ratory organs represent the porte-vent. The lips act in the strengthening and modifying the sound, in a manner similar to same manner in blowing the horn, the trumpet, and the that of the horn with tongued pipes. In the articulated voice, trombone; for it is not enough merely to blow into these or urtered word, the tongue, teeth, and lips play an important instruments, but the lips also must be put into a state of part in the pronunciation of the vowels and consonants. vibration like membraneous tongues. It is for this reason The Organ of Hearing.-The ear is the organ by means of thar mouth.pieces are used of a diameter smaller in proportion which we are made sensible of the undulations of sonorous as the sound is to be raised higher, and so that the lips may bodies, and these are transmitted by the external air to the be contracted or widened according as the sound is to be acoustic nerve. The cartilaginous external car acts like the elevated or lowered.

funnel of a hearing trumpet, of which the tube commences at The Organ of the Voice, „The voice is a sound produced in the acoustic or auditory nerve, and is hollowed out at the os tema particular organ, called the larynx, at the moment when it poralis. It is by this canal that the sonorous wares are introis traversed by the air breathed from the lungs. The larynx duced, and made to strike and put into vibration an elastic is a wide and short pipe placed between the back of the membrane stretched at the bottom of the canal, called the mouth and the trachea, or canal which conveys the air to the tympanum or drum. Beyond this membrane there is a cavity, lungs. A mucous membrane lines the interior of the larynx called the middle ear or cavity of the tympanum, which is filled and passes over two aments which have between them a with air received from the back part of the mouth by a canal triangular opening with the base behind and the vertex in called the Eustachian tube or horn. Behind this cavity, and front. These ligaments are the lower vocal cords. Above opposite to the membrana tympani, there is a membrane of the them the larynxo enlarges, then diminishes, and the mucous same kind which closes two apertures called the fenestra oralis membrane covers two new but weaker ligaments, which are and the fenestra rotunda. These two membranes are connected called the upper vocal cords, having between them an opening by a chain of small bones called the malleus, the incus, the os similar to the former. The space between each vocal cord, orbiculare, and the stapes, and put in action by two inuscles. the lower and the upper, to the right and to the left, presents The vibrations of the membrana tympani are transmitted to two cavities which are called the ventricles of the larynx. The the membrane of the fenestra ovalis by means of this osseous triangular space comprised between the vocal cords, right and chain, from the air in the cavity of the tympanum, and from left

, is called the glottis. The edges of the openings are called the bony sides of this cavity. The fenestra ovalis and the the lips of the glottis, and their distance from each other varies fenestra rotunda put this cavity in communication with the with the action of certuin muscles. Above the glottis there is vestibulum, which is placed at the end of the system of canals a kind of fibro-cartilaginous moveable valve called the epi- called the cochlea, and the three semicircular canals

, which together glottis ; it is intended to prevent, in the action of swallowing, form the labyrinth or internal ear. These canals contain & Huid the entrance into the larynx of food, solid or liquid, which, by in which the threads of the auditory nerve are immersed. The its stoppage in the wind-pipe, would occasion suffocation. vibrations of the membrane of the fenestræ are transmitted to Moreover, the apparatus of the voice is completed by the this fluid and to the auditory nerve ; and this nerve, by transbuccal cavity, the upper part of the pharynx, or opening

of mitting its impressions to the brain, realises the condition the gullet and windpipe, and the nasal apertures. In order nece ssary to the sensation of hearing, see fig. 155. that the sound of the voice may be produced, two conditions

Fig. 155. are necessary : Ist, 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. It has also been determined in what part of the larynx the A. Funnel of the External.Ear-B, Meatus Auditorius-C, the Lobe of the bound of the voice is produced. The experiments of M. Tube-X, the Cochlea-G, the Acoustic Nerve-H, the Vestibulum and Bichat and Magendie prove that it is the lower vocal cords Semicircular Canals-1, the Membrana Tympani,

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LESSONS IN CHEMISTRY.-No. XXVII.

boiling, it will be found to dissolve completely. In other words,

the white substance obtained by the addition of chloride of The Metal Lead.—The physical characteristics of this very sodium to acetate of lead is the chloride of lead, which is so useful metal are so well known, that they scarcely require de- far from being totally insoluble in water (even cold), that we scription. Soft, blueish white, possessing considerable specific

were obliged to add alcohol in order to insure its absolute pregravity, very fusible, laminable, ductile, easily tarnishing on cipitation; and is so perfectly soluble in hot water that we have exposure to air,---lead, when obtained free from combination, I been enabled to convert the former white powder into a colour. could scarcely be confounded with any other metal. Not only less solution. This precipitate, moreover, is neither whitened is lead very plentifully distributed throughout nature, but it is nor turned black by the agency of ammonia. Let us now draw a very useful metal, as the slightest reflection will demonstrate these facts into one focus and appreciate their significance. In to the student. Its combinations, however, are for the most the first place, we have already seen that there only exist two part poisonous, the amount of their power being dependent on

metals the chlorides of which possess the slightest claim to the their degree of solubility; and as lead is employed for thousands quality of insolubility: of these the protochloride of mercury of purposes involving intimate contact with articles of food and (calomel) and the chloride of silver may be regarded as abso. drink, it behoves us to be able to appreciate the conditions lutely insoluble (in water); the third, which is chloride of lead, under which this metal, so useful a servant, may become an is not absolutely insoluble. Clearly, then, it is chloride of lead insidious enemy.

we are dealing with, and consequently the metal whose soluChemical Qualities of Lead Combinations.-Combinations of this tion we are investigating must be lead. The action of ammonia metal, as of every other, admit of classing into the soluble and still further demonstrates that it can neither be chloride of silver the insoluble. For the purposes of our experiments we shall nor of mercury. However, the chemist would scarcely think it require a soluble solution, and none is better for our purposes one line of testing. He would scarcely then be warranted in

safe, in any instance, to rely implicitly on the indications of than a solution of acetate of lead, commonly called. sugar con allowing our unknown x to escape without further questioning. lead.It consists of protoxide of lead united with acetic acid. Take about as much as will lie heaped upon a fourpenny

Effect of Sulphuric Acid and soluble Sulphates on Salts of Lead.piece of crystallised sugar of lead, and dissolve it in about a Let me premise, in reference to these tests, that the sulphuric wine-glass full of common water; if pump or well-water, all the acid to be employed as a test in this instance should be fur better. Try to dissolve it, I should have said; because, as the convenience diluted, the dilution being in the ratio of about one of operator will find, perfect solution cannot be effected, but a acid and nineteen of water (by measure). As to the soluble sulwhite powder will remain. So far, then, as concerns the solution phates, the experimentalist may either employ sulphate of soda, we were desirous of making, our operation is a failure. I meant much used in veterinary practice under the name of “ Glauber's it to be a failure, in order to demonstrate a fact. The white salt,", or else sulphate of magnesia, better known as “ Epsom appearance developed is, however, not without its own signifi. salts.” Taking a little of the solution of x, add to it a portion cance, and we shall revert to it by-and-by; meantime preserve of dilute sulphuric acid, or any soluble sulphate. Remark the the whitened liquor in a properly-labelled corked bottle. heavy white precipitate which deposits. Remark, too, how

Repeating now the experiment with the substitution of pure insoluble this precipitate is in water--even hot: for if a portion distilled water for impure or common water, a solution of ab. he boiled in pure water, the clear liquid decanted, and tested solute transparency will result, if the water employed be totally with hydrosulphuric acid, not the slightest blackening results ; free from impurity; gradually, however, it will be found that an evidence so palpable as to require no comment. Remark, mere contact with atmospheric air gives rise to a certain turbi- too, that this same white precipitate is scarcely soluble, if sodity, and this for a reason we shall discover presently,

luble at all, in nitric acid, even though boiling, Having prepared our solution, let us now deal with it ana- All the facts of this line of demonstration prove that we are lyrically. Let the reader assume it to be unknown ; let him, dealing with sulphate of lead. Only one sulphate besides it for the purpose of argument, call it X. What is the x? Such has an equal amount of insolubility ; this one is the sulphate of is the question we require to solve.

baryta, which, however, is generated out of a solution neither By this time the student will know intuitively, so to speak, precipitable by chlorides nor by hydrosulphuric acid. Before the series of questions we have to demand of our unknown x leaving the sulphate of lead, let the experimentalist satisfy Is it a metal? Yes or no. If a metal, what class of metal? what himself that a precipitate identical in every respect may be section of the class ? and lastly, what metal?

generated by the substitution of a soluble sulphate for sulI need scarcely state that you will begin your testing opera- phuric acid. tion by the employment of hydrosulphuric acid in aqueous With these facts before himn_namely, with the double evisolution. It yields a black precipitate, thereby teaching us dence supplied by the agency of chlorides, on the one hand, that the solution we have to deal with not only contains a and sulphuric acid and sulphates on the other, the operator metal, but a metal of the car igenous class; teaches us, more. need not entertain a doubt as to the name of the metal" x. It over, that the metal is neither iron, manganese, uranium, must be lead. Nevertheless I shall mention further tests precobalt, or nickel, all of which require hydrosulphate of sently; not that they are required so far as our present exami. ammonia to effect their precipitation : teaches us that the nation goes, but that they might be required under other circummetal 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, let us well contemplate some practical applications which the precipitate could not be black. Gradually, then, we have admit of being made, of chemical reactions already brought narrowed the list of bodies to which our x might belong. The before us. All soluble lead compounds are poisonous, as I analyst might now, in the ordinary course of testing, employ an have already remarked; and of course all' absolutely ia, aqueous solution of ferrocyanide of potassium (prussiate of soluble ones are innocuous. Supposing, then, a naturally fatal potash) as a test; under which circumstances he would obtain a dose of acetate of lead, or any other soluble salt of that

metal, whitish precipitate-the teaching conveyed by which would be swallowed-what would be ihe antidote to the same? Our still less than that already imparted by the hydrosulphuric aim would not be to convert the soluble salt into the chloride, acid. The operator would now have recourse to "random tests;" certainly; because the latter is scarcely to be called insoluble. likely enough he would at once have recourse to a soluble We should try to convert it into the absolutely insoluble sulphate: chloride, say chloride of sodium, or common salt. Supposing but how? a solution of this substance employed--the stronger the better, To administer sulphuric acid pure would be out of the saturated by preference-he would most likely obtain from a question: to administer dilute sulphuric acid would be highly solution of acetate of lead of the strength described, a white dangerous; but the young chemist'will not fail to see that a precipitate. I say most likely, because in proportion as the soluble sulphate (Epsom salts) might be given with advantage, temperature of the lead-containing solution is higher, so is the even though administered in excess. Having, then, once estatendency less of the white precipitate to fall. Its precipitation, blished the fact of poisoning by an over-dose of lead salt, however, may be assured by adding a certain amount of alcohol administer solution of Epsom sali copiously. This is the anti(rectified spirit of wine).

dote. In our next lesson we shall resume the consideracior, of On collecting a little of this white precipitate (say a few the tests for lead solutions, and perhaps discuss the peculiarities grains), placing it in a little fask, adding pure water, and of the metal when operated upon in the dry way.

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4th. LESSONS IN BOOKKEEPING. No. XIV,

Effected by Andrew Lloyd, an insurance on

7hhds. of Sugar, valued at £25 per hhd., from
(Continued from page 230, Vol. IV.)

Berbice to London, at 3 per cent., the amount of
premium being

£5 5 0
FOREIGN TRADE.
Policy duty

O 10 Having allowed our students time to study the principles and

£5 15 6 prictice of Bookkeeping as applicable to the transactions of

4th. Hone Trade, we now proceed to lay before them a series of transactions in Foreign Trade; and afterwards to show them Effected for account of Nathan Herschell, Barbahow to enter these transactions into the proper books, as we

does, the foregoing Insurance have done in our preceding Lessons in reference to Home Premium and Policy on £175

£5 15 6 Trade. The following Memoranda of Transactions are to be Commission on do., at per cent.

0 17 6 entered in the same manner as before; Ist, All Receipts and Payments of Cash in the Cash Book. Here, however, the

£6 13 0 transactions with the Bank are to be entered along with the

6th. 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

Victoria

£175 30 unnecessary space, and the student can easily judge for himself how much money must be drawn from the Bank each day

8th. for the Payments, or how much should be lodged in the Bank from the Receipts. For this purpose, of course, he will make Effected by Andrew Lloyd, an Insurance on £700, the proper entries in the separate columns appointed for the

on 20 tierces of coffee, valued at £35 per tierce, Bank transactions as shown in the Cash Book under the Head from Berbice to London, at 25 per cent. preof Ilome Trade. This process renders it unnecessary for the mium

£17 10 0 Merchant to keep, a separate Bank account or Bank Book : Policy

1 16 9 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

£19 6 9 Business Cash transactions operate as a check on each other,

8th. the difference between these balances being always the amount

Effected for account of John Henderson, Berbice, of cash in hand.

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

£19 6 9 the Bills Receivable Book, and all Acceptances of Bills in Premium and Policy on £700

3 10 0 the Bills Payable Book. In these two books, the columns for Commission on do., at $ per cent the various particulars relating to the Bills are more numerous

£22 16 9 than those shown in the Bill Books under the head of Home

12th, 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

£1145 10 0 3rd, The particulars of all the other transactions relating to the Foreign Trade are entered in the Day Book; but many of

18th. these particulars are copied from other Books usually kept in a Merchant's Counting House ; viz. the Invoice Book, the Received in Cash for Bill No. 551 on Richard

Sykes

... £120000 Account Sales Book, the Account Current Boo , the Insurance Book, etc.

29th.
MEMORANDA OF TRANSACTIONS.
Took out of Cash for Petty Cash Account

£10 0 0 July 1st, 1854.

August 1st.

Purchased Goods of the following persons, Inventory of the Assets and Liabilities of the House of

Of Samuel Morley, 9 bales tow Osnaburgs £236 5 White, Smith and Company, Merchants, London, as per Tuelon and Co., 3 cases of hats

32 2 0 Balance Sheet of Ledger B.

£268 7 0 ASSETS.

2nd. Cash in the Union Bank

£2550 0 0 Paid Fox, Tennant and Co. the balance of their Exchequer Bills 5310 0 0

£320 15 0 Bills Receivable

7300 15 0 Three per Cents. Stock £6000 at 90 per cent. 5400 0 0

3rd, Debentures

513 0 0 Purchased Goods of the following persons, Ship Victoria, our · share

3000 0 0 Of William Phillips, shoes, amounting to £278 15 11 Adventure in Scotch Linen

2467 0 0
James Parker, linen tick,

42 0 0 Richard O'Brien and Co., Dublin

3530 12 0
Matheson and Co., platillas,

328 5 4 Peter Hutchinson and Co., Liverpool ...

1350 10 0
Thomas Barker, lint Osnaburgs

367 10 Thoinas Brown and Co., Falmouth 970 0 10

£1016 11 3 £32391 17 10

4th. LIABILITIES.

Received of Thomas Brown and Co., balance of £2350 10 0

£970 0 10 Insurance, premiums due

1880 15 0

5th, Nathan Herschell, Barbadoes

1370 5 0 John Henderson, Berbice

720 5 0 Effected by Andrew Lloyd, an Insurance on Samuel Morley, London

960 15 0 £1500, on Sundry Goods, from London to Schofield, Halse and Co., Jamaica 1150 10 0 Jamaica, at 2 per cent. premium

30 0 0 Fox, Tennant and Co., Liverpool 320 15 0 Policy

3 18 9

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LESSONS IN CHEMISTRY.-No. XXVII.

boiling, it will be found to dissolve completely. In other words,

the white substance obtained by the addition of chloride of The Metal Lead.—The physical characteristics of this very sodium to acetate of lead is the chloride of lead, which is so useful metal are so well known, that they scarcely require de. far from being totally insoluble in water (even cold), that we scription. Soft, blueish white, possessing considerable specific were obliged to add alcohol in order to insure its absolute pregravity, very fusible, laminable, ductile, easily tarnishing on

cipitation ; and is so perfectly soluble in hot water that we have exposure to air,-lead, when obtained free from combination, been enabled to convert the former white powder into a colour. could scarcely be confounded with any other metal. Not only less solution. This precipitate, moreover, is neither whitened is lead very plentifully distributed throughout nature, but it is nor turned black by the agency of ammonia. Let us now draw a very useful metal, as the slightest reflection will demonstrate these facts into one focus and appreciate their significance. In to the student. Iis combinations, however, are for the most the first place, we have already seen that there only exist two part poisonous, the amount of their power being dependent on metals the chlorides of which possess the slightest claim to the their degree of solubility; and as lead is employed for thousands quality of insolubility: of these the protochloride of mercury of purposes involving intimate contact with articles of food and (calomel) and the chloride of silver may be regarded as abso. drink, it behoves us to be able to appreciate the conditions lutely insoluble (in water); the third, which is chloride of lead, under which this metal, so useful a servant, may become an is not absolutely insoluble. Clearly, then, it is chloride of lead

we are dealing with, and consequently the metal whose soluChemical Qualities of Lead Combinations.-Combinations of this tion we are investigating must be lead. The action of ammonia metal, as of every other, admit of classing into the soluble and still further demonstrates that it can neither be chloride of silver the insoluble. For the purposes of our experiments we shall nor of mercury. However, the chemist would scarcely think it require a soluble solution, and none is better for our purposes safe, in any instance, to rely implicitly on the indications of than a solution of acetate of lead, commonly called sugar of one line of testing. He would scarcely' then be warranted in lead." It consists of protoxide of lead united with acetic acid.

allowing our unknown x to escape without further questioning.
Take about as much as will lie heaped upon a fourpenny Effect of Sulphuric Acid and soluble Sulphates on Salts of Lead.-
piece of crystallised sugar of lead, and dissolve it in about a Let me premise, in reference to these tests, that the sulphuric
wine-glass full of common water; if pump or well-water, all the acid to be employed as a test in this instance should be for
better. Try to dissolve it, I should have said ; because, as the convenience diluted, the dilution being in the ratio of about one of
operator will find, perfect solution cannot be effected, but a acid and nineteen of water (by measure). As to the soluble sul.
white powder will remain. So far, then, as concerns the solution phates, the experimentalist may either employ sulphate of soda,
we were desirous of making, our operation is a failure. I meant much used in veterinary practice under the name of Glauber's
it to be a failure, in order to demonstrate a fact. The white salt," or else sulphate of magnesia, better known as “ Epsom
appearance developed is, however, not without its own signifi. salts." Taking a little of the solution of x, add to it a portion
cance, and we shall revert to it by-and-by; meantime preserve of dilute sulphuric acid, or any soluble sulphate. Remark the
the whitened liquor in a properly-labelled corked bottle. heavy white precipitate which deposits. Remark, too, how

Repeating now the experiment with the substitution of pure insoluble this precipitate is in water-even hot: for if a portion
distilled water for impure or common water, a solution of ab. be boiled in pure water, the clear liquid decanted, and tested
solute transparency will result, if the water employed be totally with hydrosulphuric acid, not the slightest blackening results ;
free from impurity; gradually, however, it will be found that an evidence so palpable as to require no comment. °Remark,
mere contact with atmospheric air gives rise to a certain turbi. too, that this same white precipitate is scarcely soluble, if so-
dity, and this for a reason we shall discover presently.

luble at all, in nitric acid, even though boiling.
Having prepared our solution, let us now deal with it ana- All the facts of this line of demonstration prove that we are
lyrically. Let the reader assume it to be unknown ; let him, dealing with sulphate of lead. Only one sulphate besides it
for the purpose of argument, call it X. What is the x ? Such has an equal amount of insolubility ; this one is the sulphate of
is the question we require to solve.

baryta, which, however, is generated out of a solution neither
By this time the student will know intuitively, so to speak, precipitable by chlorides nor by hydrosulphuric acid. Before
the series of questions we have to demand of our unknown x. leaving the sulphate of lead, let the experimentalist satisfy
Is it a metal? Yes or no. If a metal, what class of metal; what himself that a precipitate identical in every respect may be
section of the class ? and lastly, what metal ?

generated by the substitution of a soluble sulphate for sul-
I need scarcely state that you will begin your testing opera- phuric acid.
tion by the employment of hydrosulphuric acid in aqueous With these facts before him-namely, with the double evi-
solution. It yields a black precipitate, thereby teaching us dence supplied by the agency of chlorides, on the one hand,
that the solution we have to deal with not only contains a and sulphuric acid and sulphates on the other, the operator
metal, but a metal of the car igenous class ; teaches us, more need not entertain a doubt as to the name of the metal x. It
over, that the metal is neither iron, manganese, uranium, must be lead. Nevertheless I shall mention further tests pre-
cobalt, or nickel, all of which require hydrosulphate of sently; not that they are required so far as our present exami-
ammonia to effect their precipitation : teaches is that the nation goes, but that they night be required under other circum-
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, let us well contemplate some practical applications which
the precipitate could not be black. Gradually, then, we have admit of being made, of chemical reactions already brought
narrowed the list of bodies to which our x might belong. The before us. All soluble lead compounds are poisonous, as I
analyst might now, in the ordinary course of testing, employ an have already remarked; and of course all" absolutely ia;
aqueous solution of ferrocyanide of potassium (prussiate of soluble ones are innocuous. Supposing, then, a naturally ratal
potash) as a test; under which circumstances he would obtain a dose of acetate of lead, or any other soluble salt of that metal,
whitish precipitate-the teaching conveyed by which would be swallowed – what would be ihe antidote to the same? Our
still less than that already imparted by the hydrosulphuric aim would not'be to convert the soluble salt into the chloride,
acid. The operator would now have recourse to "random tests;"' certainly; because the latter is scarcely to be called insoluble.
likely enough he would at once have recourse to a soluble We should try to convert it into the absolutely insoluble sulphate:
chloride, say chloride of sodium, or common salt. Supposing but how?
a solution of this substance employed--the stronger the better, To administer sulphuric acid pure would be out of the
saturated by preference he would most likely obtain from a question: to administer dilute sulphuric acid would be highly
solution of acetate of lead of the strength described, a white dangerous; but the young chemist'will not fail to see that a
precipitate. I say most likely, because in proportion as the soluble sulphate (Epsom salts) might be given with advantage,
temperature of the lead-containing solution is higher, so is the even though administered in excess. Having, then, once esta-
tendency less of the white precipitate to fall. Its precipitation, blished the fact of poisoning by an over-dose of lead salt,
however, may be assured by adding a certain amount of alcohol administer solution of Epsom sali copiously. This is the anti-
(rectified spirit of wine).

dote. In our next lesson we shall resume the consideratior. of
On collecting a little of this white precipitate (say a few the tests for lead solutions, and perhaps discuss the peculiarities
grains), placing it in a little flask, adding pure water, and of the metal when operated upon in the dry way.

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Ath. LESSONS IN BOOKKEEPING.-No. XIV,

Effected by Andrew Lloyd, an insurance on

7hhds. of Sugar, valued at £25 per hhd., from
(Continued from page 230, Vol. IV.)

Berbice to London, at 3 per cent., the amount of
premium being

£5 5 0
FOREIGN TRADE.
Policy duty

0 10 6 Having allowed our students time to study the principles and

£6 15 6 practice of Bookkeeping as applicable to the transaccions of

4th. Home Trade, we now proceed to lay before them a series of trinsactions in Foreign Trade; and afterwards to show them Effected for account of Nathan Herschell, Barbahow to enter these transactions into the proper books, as we

does, the foregoing Insurance have done in our preceding Lessons in reference to Home Premium and Policy on £175

£5 15 6 Trade. The following Memoranda of Transactions are to be Commission on do., at per cent.

0 17 6 entered in the same manner as before; Ist, All Receipts and Payments of Cash in the Cash Book. Here, however, the

£6 13 0 transactions with the Bank are to be entered along with the

6th. 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

Victoria

£175 30 unnecessary space, and the student can easily judge for himself how much money must be drawn from the Bank each day

Sth. for the Payments, or how much should be lodged in the Bank from the Receipts. For this purpose, of course, he will make Effected by Andrew Lloyd, an Insurance on £700, the proper entries in the separate columns appointed for the on 20 tierces of coffee, valued at £35 per tierce, Bank transactions as shown in the Cash Book under the Head from Berbice to London, at 2per cent. preof Ilome Trade. This process renders it unnecessary for the mium

£17 10 0 Merchant to keep a separate Bank account or Bank Book : Policy

1 16 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

£1969 Business Cash transactions operate as a check on each other,

8th. the difference between these balances being always the amount Effected for account of John Henderson, Berbice, of cash in hand.

the foregoing Insurance 2nd, Al Drafts and Remittances of Bills are entered in

£19 6 9 the Bills Receivable Book, and all Acceptances of Bills in Premium and Policy on £700

3 10 0 the Bills Payable Book. In these two books, the columns for Commission on do., at } per cent the various particulars relating to the Bills are more numerous

£22 16 9 than those shown in the Bill Books under the head of 1!ome

12th. 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

. £1145 100 3rd, The particulars of all the other transactions relating to the Foreign Trade are entered in the Day Book ; but many of

18th. these particulars are copied from other Books usually kept in a Merchant's Counting House ; viz. the Invoice Book, the Received in Cash fur Bill No. 551 on Richard

Sykes Account Sales Book, the Account Current Boo , the Insurance

... £1200 0 0 Book, etc.

29th.
MEMORANDA OF TRANSACTIONS.
Took out of Cash for Petty Cash Account

£10 00 July 1st, 1854.

August 1st.

Purchased Goods of the following persons, Inventory of the Assets and Liabilities of the House of

Of Samuel Morley, 9 bales tow Osnaburgs £236 5 0 White, Smith and Company, Merchants, London, as per Tuelon and Co., 3 cases of hats

32 2 0 Balance Sheet of Ledger B.

£268 7 ASSETS.

2nd. Cash in the Union Bank

. £2550 0 0 Paid Fox, Tennant and Co. the balance of their Exchequer Bills 5310 0 0

£320 15 0 Bills Receivable

7300 15 0 Three per Cents. Stock £6000 at 90 per Cent. 54000 0

3rd, Debentures

513 00Purchased Goods of the following persons, Ship Victoria, our share

3000 0 0

Of William Phillips, shoes, amounting to £278 15 11 Adventure in Scotch Linen

2467 0 0
James Parker, linen tick,

42 00 Richard O'Brien and Co., Dublin

3530 12 0
Matheson and Co., platillas,

328 5 4 Peter Hutchinson and Co., Liverpool

1350 10 0
Thomas Barker, lint Osnaburgs

367 10 0 Thomas Brown and Co., Falmouth 970 0 10

£1016 11 3 £32391 17 10

4th. LIABILITIES.

Received of Thomas Brown and Co., balance of £2350 10 0

£970 0 10 Insurance, premiums due

1880 15 0

5th. Nathan Herschell, Barbadoes

1370 5 0 John Henderson, Berbice

720 5 0 Effected by Andrew Lloyd, an Insurance on Samuel Morley, London

960 15 0 £1500, on Sundry Goods, from London to Schofield, Halse and Co., Jamaica 1150 10 0 Jamaica, at 2 per cent. premium

30 0 0 Fox, Tennant and Co., Liverpool 320 15 0 Policy

3 18 9

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