one of the Hebrews' children." We find from the monuments that the Israelites were marked by the peculiar physiognomy which characterizes the Jews of the present day, so that the instant the princess beheld the child, she was quite certain of its parentage. This is one of the minute traits which at once stamps the authenticity of a narrative, for it is one which at the first glance seems improbable, but being confirmed by undesigned coincidence, becomes the very strongest corroborative evidence.

"She called his name Moses, (which signifies, drawn out); and she said, Because I drew him out of the water." The circumstance of naming persons from some striking peculiarity must be familiar to every reader of the Old Testament.

Though "Moses was instructed in all the wisdom of the Egyptians," we find that he never forgot his parentage. It is probable, that in spite of the exalted patronage he enjoyed, the courtiers of Pharaoh failed not to remind him that he belonged to a degraded caste. This, indeed, is evident from the reproach of the Israelite whom Moses reproved for injuring one of his brethren, "Who made thee a prince and a judge over us?" In this passage, the word translated prince more properly signifies man. Now, in almost every example of a dominant caste established in a country, we find its members exclusively arrogating to themselves the title of man, as if their inferiors were below the ordinary level of humanity. Indeed, our English title baron, simply signifies man, and was introduced at the time of the Conquest, when the Normans reduced the Saxons to a state nearly as degraded as that of the Israelites during their Egyptian bondage. Nothing more forcibly proves the miserable condition of the Hebrews, than the readiness with which this delinquent adopted the reproachful language of the oppressors, and denied the title of man to the most exalted of his own nation.

The reigning Pharaoh "sought to slay Moses;" an injury to one of a ruling caste is never forgiven. Were Pharaoh inclined to pardon Moses, it is probable that he would have found such an act of clemency beyond the limits of his power; even at this day, the sultan of Turkey would find it a very hazardous experiment to spare a Raya who had struck, much less slain a Turk.

Moses fled into the land of Midian. There are two countries known by this name in Scripture; one eastwards of the Asphaltic Lake, on the confines of Moab, the other which afforded shelter to Moses, on the Elanitic Gulf of the Red Sea. The inhabitants

of the latter appear to have been a pastoral as well as a commercial race; they seem to have left the care of their flocks to women, which will account for the circumstance of the introduction of Moses to the daughters of Jethro. It may be added, that in this part of Arabia, the duty of attending the flocks is still regarded as a degrading employment by men, and generally falls on the female part of the population.

During the interval between the birth of Moses and his appearance before the sovereign of Egypt to claim permission for the children of Israel to go and worship God in the desert, the persecution of the Hebrews seems to have relaxed. A new Pharaoh most probably filled the throne, whose attention was not directed to the condition of his subjects in the land of Goshen until this application was made to him by Moses and Aaron. Pharaoh the Fourth re"Behold vived the cruel policy of his predecessor: the people of the land now are many, and ye make them rest from their burdens." (Exod. v. 5.) The respite, however, was doomed to be of no long continuance, and the tyrant soon invented a new refinement of oppression. "Ye shall no more give the people straw to make brick as heretofore: let them go and gather straw for themselves." (Exod. v. 7.) Straw is not used in the modern manufacture of bricks, but anciently it was to connect and compact bricks dried in the sun. Bricks thus formed of straw and mud are still made in Egypt, and their ancient use is proved by the numbers found in the ruins of the brick pyramids.

Pharaoh' the Fourth having thus deprivea the labourers of the materials necessary for the manufacture in which they were engaged, insisted that they should still perform their allotted tasks. "And the tale of the bricks, which they did make heretofore, ye shall lay upon them; ye shall not diminish ought thereof for they be idle: therefore they cry, saying, Let us go and sacrifice to our God. Let there be more work laid upon the men, that they may labour therein; and let them not regard vain words." (Exod. v. 8, 9.) The unfortunate Israelites were thus forced to undertake a new labour. "So the people were scattered throughout all the land of Egypt, to gather stubble instead of straw." (Exod. v. 12.) Many persons judging from our agricultural habits, might be led to suppose that Pharaoh required impossibilities; but as we have already observed in a former article of this series, the Egyptian reapers only cut off the ears of the corn, leaving the greater part of the stem untouched, so that the straw remained for

waste. Consequently, though the task imposed upon the Israelites was very severe, it was not wholly impossible.

The Israelites were unable to fulfil the double task, "And the officers of the children of Israel, which Pharaoh's task-masters had set over them, were beaten." (Exod. v. 14). This is a trait of government belonging to the oriental nations, both in ancient and modern times, but especially to such as have the misfortune to be ruled by a dominant caste. The Turk in the west of Asia, and the Mantchew Tartar in the remote east, make the stick the chief agent of administration. The highest officers of state are exposed to this infliction, which is never supposed to degrade the sufferer; on the contrary, we find many examples of viziers and nobles bastinadoed by order of their sovereign, for some slight offence or groundless suspicion, subsequently restored to favour and rank, without any one feeling that public punishment had weakened their respectability.

There are some who pretend to believe, that the accounts given by the sacred historian of the tyranny of the Pharaohs must be exaggerated; but the Fellahs of Egypt are, at the present day, subjected to oppressions similar to those described by Moses, and the remembrance of the Israelites is recalled to the mind of modern travellers, by the sufferings and the cruelties with which he is shocked at almost every step in that unhappy country.

ARSENIC.

ARSENIC is but rarely found in a state of purity. It commonly occurs in combination with the ores of cobalt, silver, lead, iron, and nickel. The minerals known by the names of realgar and orpiment, consist of Arsenic and sulphur in different proportions. The former of these native products seems to have been known to the ancients, and used by them in painting and for medicine.

Metallic Arsenic is exceedingly brittle, of a crystalline structure, and so volatile, that at a temperature of 356 degrees it is vaporised without melting. Its colour is a grayish-white, very much resembling that of polished steel, to which also its lustre bears a close analogy. This metal speedily tarnishes on being exposed to the action of air and moisture, its surface becoming covered with a film of black powder, which is sometimes superficial, whilst at other times it extends throughout the whole mass, It is said that some specimens of metallic Arsenic, which are supposed to have been in a state of extreme purity, have been kept for years in open vessels without losing their characteristic brilliancy.

Arsenic is highly inflammable, burning with a blue flame, and emitting fumes, the odour of which is very much like that of garlic. The Arsenic of commerce, commonly called white Arsenic, and by chemists arsenious acid, is a compound formed by the union of the metal with oxygen. The greater part of it is obtained from Bohemia and Saxony, where it is prepared by submitting the arsenical ores, with which those countries abound, to a strong heat in an oven, or reverberatory furnace, to which is attached a horizontal flue several hundred feet in length. In this flue the vaporised Arsenic is condensed, in the form of a dark gray powder, which is again heated, but in close iron vessels, when the impurities are separated, and the arsenious acid obtained in dense solid masses possessing a vitreous (glassy) lustre. By exposure to air, however, these semi-transparent masses gradually become opaque and fall into fine

white powder, in which state Arsenic is commonly sold at the shops.

In its metallic state Arsenic is used in the arts, but not to any great extent. It forms an alloy with copper which is very malleable, and when plated with silver susceptible of a fine polish. This alloy enters into the composition of the specula of reflecting telescopes. Arsenic is also used in the manufacture. of shot; a small quantity being mixed with the melted lead is found to impart to it the property of granulating in spherical drops. Arsenious acid is employed for purifying flint glass, whilst in a state of fusion, and for preparing colours used in painting. But for this latter purpose it is not so well adapted as the sulphurets of Arsenie already mentioned, namely, realgar and orpiment, to which we are indebted also for some very beautiful pigments used in dying and calico-printing.

Arsenic (arsenious acid) is one of the most virulent poisons with which we are acquainted, and as its cheapness renders it accessible to all classes, it has obtained an unfortunate celebrity by its frequent association with deeds of murder and suicide. Until very lately this dangerous substance has always been described as acrid and nauseous to the taste, producing a sharp burning sensation in the mouth and Arsenic posthroat. This description is erroneous. sesses hardly any taste, and what it has is sweetish, so that it is possible to swallow it without exciting suspicion or alarm. It is but slightly acted on by cold water, requiring four hundred times its own weight of that liquid for its solution. Of boiling water only thirteen times its weight is required; but on being permitted to cool the Arsenic separates from the water in the proportions just mentioned. Its solubility is greatly impaired by admixture with vegetable or animal substances, as coffee, tea, milk, and other similar materials.

Arsenic is very commonly used for destroying vermin, especially mice and rats, a practice which we think cannot be too strongly discountenanced, since it is never resorted too without considerable risk, and has often been attended by consequences the most unexpected and distressing. It is only a few months since that a poor boy lost his life by eating a piece of poisoned bread and butter, which had been incautiously left in an exposed situation as a bait for rats. And we know of numerous instances in which valuable animals have been destroyed whilst the vermin have escaped. Another objection to the use of Arsenic for the purposes just mentioned is, that it facilitates the means of obtaining it; thus placing it within the reach of persons who are too often excited by malice, revenge, or despair, and who, being familiar with its poisonous effects, resort to it as a ready instrument of destruction to themselves or the objects of their hatred. Hence it is that the number of deaths from poisoning by Arsenic, both by accident and design, very greatly exceed those occasioned by any other substance.

For medicinal purposes Arsenic has long been employed, but it requires to be administered with extreme caution, and in very minute doses; and its effects upon the system being vigilantly watched. In the hands of the ignorant or inexperienced it is scarcely possible to estimate the mischief it may produce; whilst under favourable circumstances it is acknow ledged to be, for certain diseases, a safe and valuable remedy.

Arsenic is an active ingredient in several quack medicines. Let it be particularly noticed that all preparations containing Arsenic are poisonous; whether intended to be taken internally, or to be

applied externally in the forms of lotions, plasters, or ointment. In the latter case it kills more rapidly than when taken into the stomach. Hence the danger of using the various ointments and plasters which profess to be efficacious in the cure of cancer and other similar complaints An ointment containing only one part by weight of Arsenic to thirty-two of fatty matter, was applied to a cancerous wound, the surface of which did not exceed an inch and a half in diameter, for one night only. The day following, the patient, a girl of eighteen, was seized with vomiting and violent colic, and on the second day she died with all the symptoms of having been poisoned. If we thought it necessary, we could enumerate many instances in which the most lamentable effects have accompanied the use of quack medicines. By the combined efforts of ignorance, impudence, misrepresentation and avarice, the most deleterious nostrums acquire a temporary notoriety. Their inventors very frequently become rich; whilst death, or lingering disease, is the lot of many of their credulous and misguided patrons.

Referring again to the employment of Arsenic for the most wicked and detestable of purposes, namely, the destruction of human life; we wish distinctly to state, that it is now hardly possible for any person who resorts to it with criminal intentions to escape, sooner or later, from the ignominy and punishment their guilt justly merits.

The detection of deleterious and poisonous substances in cases of sudden or suspicious illness or death, constitutes an important branch of medical jurisprudence; and there is no substance whose presence can be more satisfactorily demonstrated, and which can be more easily separated from the contents of the stomach either before or after death, than that to which we here particularly allude. By a process, the details of which would not be interesting to our general readers, but which is of the utmost importance to the chemist, as it is also to the Christian philanthropist, so small a quantity as one-twentieth of a grain of arsenic has been collected from the stomach of a person who had been poisoned. Nor must we omit to mention the antiseptic properties of arsenic, by which we mean that it preserves from decay the bodies of those whom it deprives of life. Instances are well authenticated in which the stomach and intestines of persons who had died from the effects of arsenious acid have been found, after the lapse of many months and even of years, in as perfect a state as they were at the period of dissolution. Hence we remark that the grave, instead of concealing, may be the means of preserving, evidences of guilt; and the offender, when least suspecting it, may prove the truth of that solemn declaration, "Be sure your sin will find you out.'

The effect of Arsenic upon the human body is so sudden, that unless it is speedily expelled from the stomach, there are but faint hopes of recovery. The symptoms of having swallowed this poison are the occurrence within fifteen or twenty minutes of spasmodic pains of the stomach, a sensation of heat and tightness of the head and throat, and inflammation of the eyes. To these succeed vomiting and purging, with excruciating pain of almost every part of the body, but especially of the stomach, bowels, and head. Not a moment should be lost in procuring medical assistance, and, in the mean time, the best that can be done is to excite vomiting as quickly and as easily as possible.

duce a temporary mitigation of suffering, than to neutralize the effects of the poison. Happily there have been instances in which, by skill and promptitude, life has been preserved; but when the first alarming symptoms have abated, it is a long time before the patient can be considered in a fair way towards recovery.

In an American journal (Silliman's) for May, 1836, two cases are mentioned, on the authority of Dr. Eastman of Holles, New Hampshire, U. S., in which tobacco had been employed with complete success in counteracting the usual effects of Arsenic. The first case occurred about the year 1820, and the subject of it was Sophia, the daughter of Dr. Eastman above mentioned, who ate, by mistake, some Arsenic which had been prepared for destroying rats. Painful symptoms soon led to inquiry, when the cause was immediately discovered. An elderly lady who was present, advised that the patient should be made to vomit as soon as possible, and as she had always felt a perfect loathing for tobacco, that herb was recommended as most likely to effect the desired purpose. A pipe was accordingly used, but as that did not produce nausea, Miss E. next chewed a large quantity of strong tobacco, and swallowed the juice. To the surprise of herself and her friends, this failed in exciting even a sensation of disgust; as did also a strong decoction made with hot water, of which she drank about half a pint. But not only was the tobacco ineffective, but the painful symptoms produced by the Arsenic gradually abated, and the patient began to feel well. Physicians soon afterwards arrived, when an emetic of blue vitriol (sulphate of copper) was administered, which operated moderately once. No ill consequences followed, and in a few days Miss Eastman fully recovered her health. The other case, which happened a few years afterwards in the same place, was that of a sick person, a female, who took arsenic by mistake, and she employed tobacco with the same success as already described. In this instance no emetic was taken, nor indeed any other remedy.

During the last few months, public attention has been directed towards a practice which seems to have prevailed to an alarming extent; we allude to the use of arsenic in the manufacture of certain kinds of candles. The merit of the disclosure is due, we believe, to a medical gentleman, who first mentioned the fact in a lecture delivered by him, last summer, before the Medico-Botanical Society. The subject has subsequently been very ably investigated by the gentleman already referred to, in conjunction with a committee, appointed expressly for the purpose by the Westminster Medical Society. By the report of this committee it is clearly shown, that candles containing arsenic are sold in very considerable quantities; that they are called by a variety of names each manufacturer giving them a different name; that they are represented by the parties interested in their sale as being very superior to tallow, and but little inferior to wax candles, yielding light greater in quantity, and purer in quality, than other candles; that they have platted, or, as they are sometimes called, metallic wicks, and require no snuffing. It has further been shown, that the quantity of arsenic (arsenious acid,) is found to vary considerably in different candles, and in different parts of the same candle, and that from 10 to 18 grains of this poisonous substance has been obtained from a pound weight of candles. The committee have examined

*

*These are "German Wax Lights," "Venetian Wax Candles," "Stearine Candles," Imperial Wax," "Moulded Wax," "I'ro

The injurious effects of arsenic, when diffused through the atmosphere of an apartment in which candles containing it were burning, could never for a moment be doubted by those acquainted with its properties. To set the question before the public in the strongest possible light, the committee already mentioned have conducted, with great care, a series of comparative experiments, in which birds, rabbits, and guinea-pigs were placed in boxes, and exposed, under precisely similar circumstances, to the products arising from the combustion of an equal number of candles containing arsenic, and of others which were quite pure. Our space will not permit us to give the details of these experiments; but we must not omit to mention, that they are both interesting and important, as respects the public health. During the week that these experiments were pursued, seven birds which had been exposed to the vapour of arsenical candles died, whilst the birds in the boxes where pure candles had been burning, were as gay, and ate and drank as freely, at the end of the week as they did at its commencement.

We cannot pursue this subject further. Let us, however, express a hope, that the exposure which has taken place, may lead to the immediate abandonment of a practice fraught with consequences of so dangerous a character.

AMUSEMENTS IN SCIENCE.
No. VII.
ASTRONOMY.

In many astronomical problems, the discovery of the meridian line, that is, a line passing exactly north and south, on any part of the earth's surface, is essentially necessary. When extreme accuracy is not required, the following plans are sufficiently correct.

Suppose the meridian line to be required for the purpose of constructing a sun-dial. Having firmly fixed a piece of brass or other substance, D E, fig. 1, in some place exposed to the sun, taking especial care that its surface is perfectly level and horizontal; and on the south side of this brass plate, fix a sharp-pointed piece of iron, a take two squares, B and C, and place them as shown in the engraving; the point where

they join at c will necessarily be immediately under the pointed end of the wire; take this point as a centre and inscribe several concentric circles. Fig. 2 will explain this better. D is the point immediately under the point of the iron, and round this point several circles are drawn. An hour or two before noon mark the spot where the shadow of the iron point passes any of the circles; an hour or two after mid-day perform the same operation.

Let us suppose A and B the points on the same circle where the shadow crossed in the forenoon and the afternoon. Take the point c exactly midway between

A and B, and from it draw a line through the centre of the circle at D. This line C D E is the meridian line of the place, and if care has been taken, its error will not be more than half a degree. The meridian line being once found, the construction of the sundial can be effected without difficulty.

IF two men are born on the same day and hour, and die on the same day and hour, one shall appear to have lived one or even two days longer than the other. It is well known to all navigators, that if a ship sails round the world, going from east to west, those on board, when they return, will have counted a day less than the inhabitants of the country they have sailed from, and to which they have returned. The cause of this is, that the vessel following the course of the sun, has the days longer, and in the whole number of the days reckoned during the voyage, there is necessarily one rising and setting of the sun less, visible to the crew. On the other hand, if the ship proceeds round the world from west to east, as it goes to meet the sun, the days are shorter, and during the whole circumnavigation, the people on board necessarily count one revolution of the sun more.

Supposing then, that of twin brothers one embarks on board a vessel which sails round the world from east to west and the other remains at home. When the ship returns, the inhabitants will reckon the day Thursday, while those on board the vessel will reckon it only Wednesday, and the twin who has been at sea will appear to have a day less in his life than he who has remained on shore. Consequently if they should die the same day, one of them would count a day less than the other, although they were both born on the same day.

But suppose that while one was sailing from east to west, the other went round the globe from west to east; on their return their account of the time would differ by two days,-one would appear two days older than the other.

Fig. 3.

D

THE Polar Star is nearly due north, and when neither sun nor moon are visible, and no mariner's compass at hand, it has directed the course of seamen across the trackless ocean, or been a guide to the wanderer on the land. Round this star the whole of the heavens appear to revolve. As it is not a peculiarly bright star, its beauty is not likely to attract notice, but it can be easily found by means of the splendid constellation of the Great Bear or Charles' Wain. This constellation is so extremely beautiful that it cannot fail to have been noticed by the most casual observer. The following figure will show the method of finding the Pole Star by means of the Great Bear. A B C represents this constellation. The two stars B and A are called the Pointers, and if a line is drawn through these in the direction of a smaller constellation, E, resembling the Great Bear in the arrangement of its stars, and known by the name of the Little Bear, the line will pass immediately under the Pole Star D. It is, as we have said, not very brilliant, but there are no stars of greater magnitude than itself within a considerable space of the heavens, for the remaining stars of the constellation of which it forms a portion, are much smaller, and only visible when the sky is particularly

clear.

LONDON:

JOHN WILLIAM PARKER WEST STRAND.