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Βαθυς, εια, υ, deep. [some. Βαρύς, εια, ν, heavy, burdenΠρεσβυς, ὁ (the only cases besides the nom. are acc. πoεσßuv, and voс. πрεσßʊ; in the plur. Tρεoßεis), old, an old man.

Ωκυς, εια, υ, swift.

Aσlevns, εs, powerless, weak. Εγκράτης, ες, self-controlled, abstinent.

Ευσεβης, ες, pious.

Ευχαρις, ι (g. ἴτος), attractive. Opfos, n, ov, straight, right. Αιτνη, ης, ή Ætna.

Arvxia, aç, n, misfortune. Αφρωδίτη, ης, ή, Aphrodite (Venus). 'Hẞn, ns, ǹ, youth. 'Opun, ns, , impulse, eagerness, zeal. Kρirias, ov, ô, Critias. Μεσοτης, ητος, ή, the middle, moderation.

Νοημα, ατος, το, a thought (something in the νους, mind).

Παρερχομαι, I pass by.
Auta, suddenly.
Ουδε, nor.

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Old age is very burdensome. Nothing is swifter than thought. Moderation is the safest No bird is blacker than the raven. The boy is swift, the man is swifter, the horse is swiftest. The horse is swifter than the man; the man is swifter than The the boy. Youth is more attractive than old age. Ethiopians are very black. No one of the Athenians was more self-controlled than Socrates. Critics was more given to plunder (robbing) than Alexander. Nothing is more pleasing than beautiful flowers.

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Sold at Liverpool, by the agency of Thomas Jones, 24 bales of Madras Cotton

Net 8580lbs at 6d. per lb.
His Commission and other expenses

18th.

£330 16 0

£20 0 0

£232 7 6 5 16 2. £226 11 4

Drew out of the London and Westminster Bank £190 0 0

18th.

Paid Osmond and Co., of London,

For Cotton bought of them on the 4th inst. 20th.

Sold Lloyd and Co., of Manchester,
24 bales of Madras Cotton (on credit)
Net 8216lbs. at 61⁄2d, per lb.
Incidental expenses

£183 4 3

£222 10 4

0 19 6

£223 9 10

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£186 0 0 2 15 9

Received of Lloyd and Co., of Liverpool,

No. 2, drawn on Warwick and Co., due May 15th £120 10 0 No. 3, drawn on Thiselton and Co., due

25th.

£183 4 3 Drew out of the London and Westminster Bank £330 0 0

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-10th.

Received in Cash for Bill No. 4, Parker and Co. £190 10 6 Deposited in the London and Westminster Bank £100 0 0

11th.

Took out of Cash for Petty Cash

11th.

29th.

£10 0 0 Received in cash for Bill No. 7, Welch and Co., £10010 O 30th.

Deposited in the London and Westminster Bank £180 0 0 Deposited in the London and Westminster Bank £100 0 0 00

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3rd.

Paid Bill No. 3, Smith and Co.

...

...

£57 8 9

5th.

Received in Cash for Bill No. 14, Margetson
and Co.,

Drew out of the London and Westminster Bank £100 0 0 Deposited in the London and Wes mi ster Bank £250 0 0
30th.
£135 18 9 Made up the account of Petty Cash from Jan, 1st
'till this day

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Received in Cash for Bill No. 6, Abrahams and Co. £113 1 0 6th.

Deposited in the London and Westminster Bank £100 0 0 7th.

Received in Cash for Bill No. 15, Warner and Co., £200 00 7th.

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LESSONS IN CHEMISTRY.-No. VIII.
WHITE arsenic (arsenious acid) is not very soluble in water, but
it readily dissolves in potash solution: add, therefore, about
Deposited in the London and Westminster Bank £200 0 0 fifteen or twenty drops of liquor potasse to about a wine-glassful

10th.

of distilled water, and place the fluid in a widish-mouthed bottle, capable of holding about four wine-glasses full-that is to say, a Received in Cash for Bill No. 16, Russell and Co., £200 0 0 bottle having a capacity of about six fluid ounces. Instead of a bottle of this kind, a clean Florence flask may be employed, and Deposited in the London and Westminster Bank £200 0 0 flask to be used, I shall construct my diagram accordingly, fig. 42. probably it will be the better of the two. Assuming a Florence

10th.

11th.

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16th.

B is the bottle in which the arseniuretted hydrogen gas is to ne Received in Cash for Bill No. 1, Allison and Co., £150 0 6 generated by mixing together zinc, dilute sulphuric acid, and liquor arsenicalis; t the tobacco-pipe shank, and ƒ the flame produced by the burning gas; T is a thin bent glass tube, through Deposited in the London and Westminster Bank £150 0 0 which the products of combustion (water and arsenical fumes)

16th.

18th.

pass into the Florence flask F. The tube bends downwards in the
flask until it nearly touches, but not quite, the potash solution.

Received in Cash for Bill No. 10, Payne and Co., £37 0 8 By this arrangement most of the arsenic enters the bent tube in

18th.,

Deposited in the London and Westminster Bank

21st.

the state of arsenious acid, passes along the tube, comes in contact with the potash solution, and is by the latter eventually absorbed. £40 0 0 During the progress of the operation it will be well, from time to time, to agitate the Florence flask in order to facilitate absorption of the gas.

Received in Cash for Bill No. 12, Baring and Co., £41 5

2

The student must not imagine that by the arrangement at

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apparatus just described all the arsenic contained in the liquor | although acetic acid in distinct excess should have been added, arsenicalis will be collected. Some portion will inevitably escape. boil the liquid for a few seconds in a shallow vessel, when a preWere it our object to collect absolutely all, other methods must be cipitate will certainly ensue. The proper vessel for conducting had recourse to: I wish the reader, however, to understand that the boiling operation is a porcelain evaporating dish, fig. 43; but these lessons involve qualitative, not quantitative chemistry-the an enamelled saucepan will answer perfectly well. latter department of the science being a subject for future consideration. It so happens, however, that a great number of the practical chemical operations having reference to arsenic involve qualitative rather than quantitative questions-the question being not so much to determine the exact quantity of arsenic present as whether it exists at all. The operátor will soon see how every particle of arsenic might be collected and estimated if desired.

Before passing on to a further consideration of our arsenical solution, just reflect for an instant on the elegant power of analysis with which the property of arsenic to combine with hydrogen and form a gas furnishes us. Hereafter a few other instances of the separation of solid bodies from each other, by converting one into a gas, will be made known. Flint is one of these. This hard, heavy, apparently untractable substance, can be readily made to assume the form of a gas.

Experiments with the Arsenical Solution. However much we have been discursively beating about since we first commenced these lessons with the examination of a metal, I trust you have not forgotten two or three red-letter rules mentioned some time back. I will repeat them: they are as follows:Metals are divided into

Kaligenous,

Fig. 43.

I stated a short time since that the method of obtaining every portion of arsenic from a liquid containing it would soon be made evident. This is the method. The arsenical solution being brought to the proper condition, that is to say, perfectly neutral, or else acidulated with acetic acid, hydrosulphuric acid is passed through it; the liquid boiled and filtered; all the arsenic is obtained in the condition of sulphuret upon the filter. Instead of filtration, decantation may, in many instances, be profitably adopted. Decantation consists in the pouring away of a liquid from a sediment, and is best conducted by means of what chemists term a Phillips's testglass-a vessel of this form, fig. 44. Owing to its peculiar construction,

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Terrigenous,

Calcigenous.

The latter class contains all the substances we commonly term metals.

All calcigenous metallic solutions yield a precipitate, either with hydiosulphuric acid, hydrosulphate of ammonia, or yellow prussiate of potash-generally with all these.

The normal colour of precipitate with hydrosulphuric acid or hydrosulphurate of ammonia is black; but two metals yield a white, and four a yellow precipitate.

Solutions of all calcigenous metals, save five, yield precipitates with hydrosulphuric acid alone.

Five do not; but they yield a precipitate with hydrosulphate of ammonia. They are iron, manganese, uranium, cobalt, and

nickel.

Now commence the operation of testing. Transfer the arsenical solution from the Florence flask to a tall wine-glass or a bottle, and transmit through it sulphuretted hydrogen gas. Most probably you will have no precipitate; and possibly you will infer that hydrosulphuric acid is incapable of furnishing a precipitate with an arsenical solution. Do not arrive at any such hasty conclusion: we will proceed to examine the conditions of this liquid. In the first place, is it alkaline? Try it by means of a piece of reddened litmus paper, or a piece of yellow tissue-paper,-you have been already instructed as to the changes on these which alkalinites would produce. Do not, however, dip the paper into the liquid-that is a dirty plan, only followed by slovenly people. Lay the slip of paper, previously moistened with distilled water, upon a little slip of clean window-glass; then dip the end of a glass rod into the fluid, from which withdraw a small quantity, and apply it to the paper.

This is the proper way to conduct the operation. Well, if the solution be alkaline, we have a sufficient explanation of the reason why no precipitate ensued; for sulphuret of arsenic, like most other sulphurets, refuses to fall in the presence of alkalies: the greater number of acids also prevent its falling, but acetic acid is an exception to this rule: therefore add acetic acid to the arsenical solution until the liquid, on being tested with blue litmuspaper, manifests distinct signs of acidity. Now transmit through it a current of hydrosulphuric acid gas, as already directed, and you will have a result, but the kind of result will depend upon

circumstances. If the amount of arsenic contained in the solution be less than a certain amount, precipitation does not immediately ensue, but the fluid is tinged yellow. Now, why is this? The explanation has already been given. I have already said, that sulphuret of arsenic is soluble in the greater number of acids. Well, even hydrosulphuric acid gas is not an exception to this rule. A certain definite portion of this acid throws down the arsenic in an insoluble form, but an excess redissolves that precipitate. If, therefore, you obtain a solution which is merely tinged yellow,

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I need hardly say that no precipitate can be considered pure until it has been frequently washed by distilled water, and the water separated, either by decantation or filtering.

If the process of filtering be adopted, and circumstances make it requisite to separate the precipitate from the filter, it may be effected by holding the unfolded filter lightly between the thumb and finger over an evaporating dish, and directing against the filter a powerful but minute jet of water by means of an apparatus already detailed, and here represented, fig. 46. The nature of the combination is such, that air being forced by the mouth down the tube t, water emerges through the jet t against the filter.

In the greater number of operations, however, we do not

require to effect the separation of a precipitate from its filter. lamp, fig. 48, fuse it at the point t, revolving it all the time heat is Our operations being qualitative, a sufficient quantity of the pre-applied. Separate the two ends by gentle extension, then twist

Fig. 46.

the tubes in reverse directions, so as to obliterate the capilary orifice at t; break the filament, and continuing to apply the point of a spirit-lamp flame, finish by making a tube like that represented in the following diagram, fig. 49, about the diameter there given, but almost twice the length. In all probability you will not be able to finish off the tube so neatly as represented-most likely you will have a bead of glass at the closed end like

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Fig. 49.

cipitate for our future purposes could have been separated from the filter by mere scraping. I would strongly advise the student, however, not to neglect the practice of learning how to remove the precipitate from the paper in the manner detailed; of course the sulphuret will be found in the evaporating dish, mixed with a great deal of water. As much as convenient of the water is now to be poured off, and the remainder dissipated by gentle evaporation over a steam or water-bath; the sulphuret will then be obtained dry and pure. It is almost superfluous to state, that the steam or water bath may be a saucepan containing water, over the mouth of which the basin or evaporating dish is laid, as represented in the accompanying diagram, fig. 47.

Fig. 47.

this. To get rid of this bead entirely requires some practice and address: take no heed of it, therefore. I shall hereafter give more specific directions for working glass, by attending to which the disfigurement may be prevented; meantime, the tube you have succeeded in forming will answer the purposes intended. Incorporate by a pestle and mortar, or on a piece of paper with a knife, the sulphuret of arsenic you have made, and dried, with about its own weight of a mixture of powdered charcoal and carbonate of soda (washing soda) in equal proportions; then carefully throw the mixture into the closed tube thus prepared, in such a manner that its sides may not remain soiled-to remove which soiling, a feather may be used-but whatever be the plan adopted, the sides.of the tube must be made quite clean.

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If now the flame of a spirit-lamp be applied to the tube containing the mixture of sulphuret, carbonate of soda, and charcoal -the tube being beld by a slip of thick paper wound round itthe first effect will be the evolution of watery vapour, which, on riging, will dim the tube, fig. 50. The operator should carefully remove it by means of a strip of blotting-paper, otherwise it might trickle back, and, falling on the hottest part of the tube, break it. The next effect will be the decomposition of the sulphuret of arsenic into metallic arsenic and arsenious acid (white areenic); the former coating the tube with a resplendent metallic ring a, b, the latter appearing as white crystalline (octagonal) particles further up c, d towards the mouth of the tube. By applying the spiritlamp flame carefully to the ring a, b, the arsenic of which it is composed may be readily volatilised, and partially converted, by combination with atmospheric oxygen, into arsenious acid; and by repeating the operation sufficiently often, the total conversion of the metal into the acid or oxide (white arsenic) may be readily accomplished.

This volatility of the crust of metallic arsenic is a character of vast importance, distinguishing arsenic from everything else. I am aware that books-especially medico-legal books-state that various stains which occur in the substance of glass, and also

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