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CHEMISTRY.-No. XV.

acid, with a smallquantity of muriatic, and ACIDS.NO. II.

distilling the solution to dryness. It is a PHOSPHORIC Acid is a compound of remarkably active poison. oxygen and phosphorus, in the proportion Tungstic Acid, a compound of tungof 20 parts of oxygen, to 15 71 of phos- sten and oxygen, is a tasteless yellow phorus. It was formerly produced by powder, insoluble in water, and is found burning phosphorus in oxygen gas, but it is native in a mineral called wolfram. It now chiefly obtained from animal bones. dissolves several of the metals. When pure, it is formed in white and Molybdic, CHROMIC, and TELLURIC snowy flakes ; but when exposed to the air, Acids, are composed of molybdenum, it attracts the aqueous vapour, and becomes chromium, and tellurium with oxygen, and a dense fluid. The phosphorus acid con- belong to the class of acids we have been tains a smaller proportion ofoxygen than the examining ; but they do not possess any phosphoric, and may be produced by the useful properties, and need not therefore slow combustion of phosphorus in oxygen be described. gas. These acids have not been applied The acids belonging to the second class to any important use.

are chiefly of vegetable origin, and contain MURIATIC Acid is obtained from sea more than two elementary substances, salt, and is a combination of chlorine and which are commonly oxygen, hydrogen, hydrogen. It has a yellowish colour, and and carbon, and occasionally a portion emits white fumes of a disagreeable and of nitrogen. suffocating smell. It is one of the most When saccharine liquors have passed corrosive of all the acids, and has a very from the first or vinous fermentation to strong affinity for water and silver. It is the second or acetous fermentation, an generally employed as a test for silver, and acid may be obtained from them, called however small may be the quantity of sil- the acetic acid. Vinegar is a diluted acetic ver held in solution, it will be instantly de- acid, but when pure and concentrated it tected by a drop of muriatic acid. This is colourless, has a pungent and acrid acid is extensively used in the arts, and it taste, and is of a volatile and corrosive may be worthy of notice, that in a diluted nature. Pyroligneous acid is a substate it may be employed for removing ink stance possessed of the same properties, stains from books without affecting the and is produced by the destructive distilprint.

lation of vegetable matter. It is, however, Fluoric Acid is a compound of fuorine extremely impure, being combined with and hydrogen,and is obtained from a mineral tar, and a nauseous empyreumatic vegesubstance called fluor-spar. Its smell has table oil, though it may be purified and a great resemblance to that of muriatic used as a substitute for vinegar. Pure acid. A remarkable and distinctive pro-acetic acid consists of twenty-four parts perty of this acid is its power of corroding of carbon, twenty-four of oxygen, and silica, and thus destroying the transparency three of hydrogen. of glass, and it is consequently used for Oxalic Acid is composed of twentyetching on this substance.

four parts of oxygen with twelve of .carBoracic Acid is composed of boron bon, and is found in the juice of sorrel and oxygen, in the proportion of one part and in the roots of rhubarb. It

may

also of the former to two parts of the latter. be obtained from sugar, and has hence The taste of this acid is at first sour, then been sometimes called acid of sugar. It bitter, and at last it leaves a sweet flavour is an extremely active poison, and proon the palate. When united with sul- duces almost instantaneous death. It is phuric acid, it emits a smell greatly resem- extensively used by calico-printers, and is bling musk. It is obtained in the form of often employed to detect the presence of thin scales, and combines with the alka- lime, for which substance it has a greater lies, and with some of the earths and me- affinity than any other acid. If a few tallic oxides. It gives to turmeric paper drops of the solution of oxalic acid be a brown colour, similar to that produced dropped into a neutral solution of muriate by the alkalies, but it reddens litmus of lime, a precipitate will be immediately paper, and gives a green colour to flame. formed, which is the oxalate of lime. But

ARSENIC ACID was discovered by it is always necessary that there should not Scheele, and consists of arsenic and oxy- be an excess of muriatic acid, for the lime gen. It is a white heavy substance, ob- would then be re-dissolved. If a person tained by dissolving common white arse has taken oxalic acid into the stomach, pownic (arsenious acid) in concentric nitric dered chalk, or magnesia in water, should be immediately administered in large doses, | disadvantages, which are sufficient to raise and the operation of the poison may thus expectation for the future, and to remove be generally prevented.

every idea of their natural inferiority to the white man.

NEGROES AND PEOPLE OF COLOUR.
A LETTER dated, some months ago, Ann

INSECTS.No. XXXIX.
Harbour, Michigan, from Mr. Metzgar,

(Taste.) a Lutheran clergyman, gives an account Taste is absolutely necessary to the conof the disrespectful conduct of the Ame- tinuance of animal existence. In cattle, ricans towards Mrs. Metzgar, simply be- and animals which feed on green herbs, cause the colour of her skin was less fair the tongue is both large and studded with than their eye had been accustomed to. large papillæ or tasters, abundantly moistThe perusal of this drew my attention to a ened with saliva, and also with a peculiar statement made by Sir Everard Home, mucus. In herbivorous animals this arsome years ago, on the utility of the black rangement is peculiarly necessary, for the substance in the skin of the negro, in pre- variety of herbs is so great, and they often venting the scorching, operation of the grow so promiscuously together, that had sun's rays; and as we know that nothing not cattle a great acuteness of taste, they tends more to the removal of prejudice, might soon be poisoned. This, however, than the rectification of the judgment upon very rarely happens. those points upon which it may have been The tongue of insects lies between the warped by false impressions, it is possible two lips, the labrum and labium. On its that some might be induced to look with upper side, at the base, it meets the palate respect and benevolence upon those they or roof of the mouth, below which it is athave hitherto slighted, when they con- tached, it may be presumed, by its roots to sider that the very colour which has the crust of the head, on each side the awakened contrary dispositions, is an in- pharynx or swallow; and on its lower side, dication of the peculiar care of our heaven- in many cases, it is attached to the labium, ly Father over this portion of our fellow and that very closely, so as to appear to be creatures.

merely a part of it, and to form its extreSome time ago, Sir Everard Home, at a mity; but in others it is more free, and in meeting of the Royal Society, showed form somewhat resembling the tongue of that by exposing the back of the hand or quadrupeds. “When ants are disposed to other parts of the body to the sun's rays, drink,” says M. P. Huber," there comes they become irritated and inflamed; small out from between their lower jaws, which specks or freckles first appear, and these on are much shorter than the upper, a minute, continual exposure rise into blisters. The conical, fleshy, yellowish process, which same is true, if the flesh be covered with performs the office of a tongue, being thin white linen; but if the body be covered pushed out and drawn in alternately : it with a piece of black crape, though it will appears to proceed from the lower lip. be hotter when exposed to the sun, yet the This lip has the power of moving itself rays will no longer produce blisters. Thus forwards in conjunction with the lower the injurious effect of the heat of the sun jaws : and when the insect wishes to lap, may be prevented by an artificial blacken- all this apparatus moves forward ; so that ing of the skin. How strongly does this the tongue, which is very short, does not show that the black man, though too often require to lengthen itself much to reach the contemptuously treated by his fellow crea- liquid.” What a curious structure to tures, is not beneath the notice of his meet the necessities and comfort of these Creator; rather may we consider him as little creatures ! continually carrying about with him, in Insects, it seems, are even nicer than the colour of his skin, the memento of his cattle in their selection of food, and conseheavenly Father's mercy.

quently in the acuteness of their taste. The depressed and degrading circum- The caterpillar of the antler moth, (charæas stances to which negroes and people of graminis,) though it feeds on a variety of colour have hitherto been subjected, have grasses, and sometimes ravages to so great been very unfavourable to the develope- an extent the meadows of Sweden, as to ment of their moral and intellectual cha- endanger the lives of the cattle for want of racter; but many instances of talent and food, does not touch the fox-tail grass, piety have appeared, notwithstanding these though to us its leaves taste little, if at all

different from some of those it so greedily | force the insect can exert. But when some devours. Other creatures confine them- sugar has been placed on the outside of a selves to only one species of grass. window, while observation has been carried

The bee-mite, though not very easily dis- forward through a magnifying glass in the lodged while the bee is alive, scampers off inside, it has been seen that the fly lets fall as soon as the bee dies, and even long before, a drop of fluid occasionally on the sugar, in when it becomes sickly from the irritation order to melt it, and thereby render it fit to of the numbers by which it is infested. be sucked up, just as we moisten a mouthWhether this arises from their finding it ful of dry bread with saliva, to fit it for more difficult to penetrate the skin, or from being swallowed. their not relishing the diseased fluids, we Vessels which supply the saliva in cannot tell; but the latter is the more pro- more than one species of insects, seem to bable reason, from the singular fact, that have been first observed by Swammerdam, Aleas and other parasitic insects never infest in the small tortoise-shell butterfly, vanessa a person who is near death; a fact that has urticæ ; but as he could not trace their terbeen so frequently observed, that it has mination, he says, with his usual scrupubecome one of the popular signs of ap- lous caution, “what the office of these proaching dissolution.

vessels is, and whether they may not be the Perhaps,” says the elder Huber," the salivary ducts, I cannot take upon me to sense of taste is the least perfect of those determine.” Lyonnet afterwards discoenjoyed by bees; for, contrary to the re- vered a conspicuous pair of these vessels in ceived opinion, they display little choice in the caterpillar of the goac-moth, (cossus collecting honey; nor do they testify ligniperda,) distinct from the silk reservoirs, greater nicety in the quality of their water, with which Swammerdam was inclined to for the most corrupted marshes and ditches confound them, and their existence has seem to be preferred to the most limpid been placed beyond all doubt by Ramdohr, streams, nay, even to dew itself. Nothing, to whom we are indebted for the following therefore, is more unequal than the quality interesting facts. of honey, the produce of one district differ- “ The pipes which carry the saliva do ing from another, and the honey of spring not always open into the mouth, but somebeing unlike that of autumn; while even times into the gullet, as in a sort of bug, the contents of one hive do not always (pentatima,) and sometimes into the storesemble those of the one which is con- mach itself, as in the bee-flies. It is remarktiguous. But though bees are thus not able that the latter insects, from feeding very choice in their nutriment, and are by exclusively on the nectar of flowers, do not no means delicate in regard to the quality require a supply of saliva to moisten their of honey, they are far from being indifferent food in the first instance, though it appears with regard to the quantity. They soon to be indispensable to digestion; while in discover, and consequently frequent, the bugs, which feed on vegetable and animal places where most is to be found; and they juices, one pipe opens into the sucker, to quit their hive much less in regard to the enable the animal to soften, if necessary, fineness or temperature of the weather, than the skin it has to pierce through, and anoaccording to their prospect of a plentiful ther into the stomach or gullet to aid dior a scanty collection. When the lime- gestion. In the common fly again, and tree and blackthorn blossom, they brave the gad-fly, both pipes open into the the rain, departing before sun-rise, and sucker, and we have already seen the ingereturning later than ordinary; but this nious use which is made of this when the activity soon relaxes; when the flowers insect feeds on dry sugar. In the waterbegin to fade, and when the scythe has cut scorpion, there are no fewer than six of down the fields of clover, the bees are these vessels, though it is rare that there are seldom tempted to go from their home by more than two in other insects. It is wor.. the most brilliant sunshine."

thy of remark, that the exterior double pair

: Man possesses salivary fountains for in it is found, when highly magnified, to moistening his organs of taste, and an ana- consist of little globules resembling a bunch logous structure is discoverable in insects. of currants; and a similar structure has Thus a fly contrives to suck up through its also been detected in one of the bee-flies, narrow haustellum a bit of dry lump-sugar; precisely like what occurs in our own saliand for this it seems unprepared, as the vary fountains.” small crystals are not only unfitted to pass, Ants are very fond of water. One of from their angular form, but adhere too them has been seen quafting a drop of dew closely together to be separated by any almost as large as its whole body; and when those in glass formicaries have water of the general welfare of the community as given them, they seem quite insatiable in they are fatal to the happiness of individrinking it; a circumstance well shown in duals. Ainong others, the following effects the following anecdote from Huber : may be distinctly traced :

“ The feet,” he says, “of my artificial The destruction of an immense amount formicary (abode of the ants) were plunged of wholesome and nutritious grain, given by in vessels constantly filled with water. This, a bountiful Providence for the food of man, which was originally adopted to prevent which is now converted by distillation into the escape of the inmates, proved to them a poison; the highest medical authorities, a fruitful source of enjoyment, by supply- examined in great numbers before your ing them with a plentiful beverage during Committee, being uniform in their testithe heats of summer. One day, while mony that ardent spirits are absolutely poithey were assembled at this fosse of the sonous to the human constitution; that in formicary, occupied in licking up the little no case whatever are they necessary, or drops which filtered between the fibres of even useful to persons in health; that they the wood, which they preferred to taking it are always in every case, and to the smallest from the basin itself, I amused myself in extent, deleterious, pernicious, or destrucdisturbing them, upon which the greater tive, according to the proportions in which number ascer:ded ; but a few remained, they may be taken into the system ; so that whom my presence had not alarmed, and not only is an immense amount of human who continued carousing. One of those, food destroyed in such a manner as to inhowever, who had regained the nest, came jure greatly the agricultural producers theinback, and approached another, apparently selves, for whose grain, but for this perquite absorbed in the pleasure of drinking. verted and mistaken use of it, there would It pushed the drinker with its mandibles be more than twice the present demand for several times successively, raising and low- the use of the now scanty-fed people, who ering its head alternately, and at length would then have healthy appetites 10 consucceeded in driving it off. The officious ant sume, and improved means to purchase then reached another similarly engaged, with nutriment for themselves and children, in whom it found no less difficulty; at length, grain as well as in all other varied producbeing persuaded of the necessity of with- tions of the earth. drawing, the drinker passed precipitately The loss of productive labour in every to the bell glass. A third, warned in the department of occupation to the extent of at same manner and by the same ant, quickly least one day in six throughout the kingregained the nest; but a fourth remained dom, (as testified by witnesses engaged in alone at the water's edge, and would not various manufacturing operations,) by which retire, nor pay any attention to the reiterated the national wealth, created as it chiefly is by blows of its friendly monitor, who at length labour, is retarded or suppressed to the exseized it by one of its legs and dragged it tent of £1,000,000 out of every £6,000,000 away rather roughly. The toper, however, that is produced ; to say nothing of the returned, keeping his large mandibles ex- constant derangement, imperfection, and tended with all the appearance of rage, and destruction in almost every agricultural again stationed himself to quaff the de- and manufacturing process, occasioned by lightful beverage; but its companion would the intemperance and consequent unskilfulgive it no quarter, and, coming in front, it ness, inattention, and neglect of those afseized it, and dragged it by main force to fected by intoxication, producing great inthe nest.

jury to our domestic and foreign trade.

The extensive loss of property by sea from shipwrecks, founderings, fires, and

innumerable other accidents, many of PARLIAMENTARY PAPER ON

which, according to the evidence of the

most experienced shipowners, mercantile From the Report of the Select Committee of Inquiry men, and others, examined by your Comon Drunkenness, appointed by the House of mittee, are clearly traceable to drunkenness

in some of the parties employed in the naThat in a national point of view, as vigation and charge of such vessels, whose affecting the wealth, resources, strength, vigilance, had they been sober, would have honour, and prosperity of the country, the been sufficient safeguards against their occonsequences of intoxication and intemperate currence. habits among the people are as destructive The comparative inefficiency of the navy

DRUNKENNESS.

and army; in both of which, according to | ing, and the rates of postage that were then the testimony of eminent naval and military fixed were continued till the reign of officers examined by your Committee, in- Queen Anne. Mails were, however, down temperance is a cankerworm that eats away to 1784, conveyed either on horseback or its strength and its discipline to the core; it in small carts ; and instead of being the being proved beyond all question that one- most expeditious and safest conveyance, the sixth of the effective strength of the navy, post had become, at the latter period, one and a much greater proportion of the army, of the slowest and most easily robbed of is as much destroyed as if the men were any in the country. In 1784, the coaches slain in battle by that most powerful ally of accomplished the journey from London to death, intoxicating drinks; and that the Bath in seventeen hours, while the post greater number of accidents occurring in took forty hours. This great disproporboth branches of the service, seven-eighths tion gave rise to the establishment of mailof the sickness, invalidings, and discharges coaches, and such is their regularity at for incapacity, and nine-tenths of all the the present time that a post-office regulaacts of insubordination, and the fearful pu- tion fixes to a minute, and in more than nishments and executions to which these

one instance to half a minute, the time at give rise, are to be ascribed to drunkenness which the mails are to arrive at the several alone.

towns and villages on the road. That the mere pecuniary loss to the The number of letters and newspapers nation from these several causes already conveyed to the British post-office is imenumerated ; namely, the destruction of mense. The letters, only, despatched from an immense amount of grain subjected 0 London, may, we believe, be estimated to distillation, the abstraction of prod. ctive average about forty thousand a day; and labour from the community, the diminished the postage sometimes exceeds two thouefficiency of the navy and army, the de- sand five hundred pounds in a single crease and deterioration of the physical and morning: yet so complete are the arrangemental powers of the population, the in- ments at the post-office, that forty-four crease of pauperism, the spread of crime, thousand letters have been sorted and and the retardation of improvement, caused marked by one hundred and five persons by the excessive use of intoxicating drinks, in the space of forty-five minutes. There may be fairly estimated at little short of may, in all, be about three thousand per£50,000,000 sterling per annum.

sons employed in the carriage and distribution of letters in Great Britain only ; besides about one hundred and eighty coaches, and from four thousand to five thousand horses. The sum produced by the

postage has, of course, progressively inThe post-office was not established increased since the establishment of the England till the seventeenth century. post-office. Thus it was, Post-masters, indeed, existed in more ancient times ; but their business was con

In 1722

£ 204,804

In 1800 fined to the furnishing of post-horses to

1,083,950 In 1814

2,005,987 persons who were desirous of travelling expeditiously, and to the despatching of since which year it has varied but little. extraordinary packets upon special occa- After all deductions of expenses, the nett sions. In 1635, Charles I. erected a letter- profit to government amounts to about office for England and Scotland; but this one million three hundred and fifty thouextended only to a few of the principal sand pounds a year. roads, the times of carriage were uncertain, and the post-masters on each road were required to furnish horses for the conveyance of letters at the rate of two- BREAD made out of wheat flour, when pence halfpenny a mile. This plan did first taken out of the oven or skillet, is unnot succeed ; and, at length, a post-office prepared for the stomach

It should go for the weekly conveyance of letters to all through a change, or ripen before it is parts of the kingdom was established in Young persons, or persons in the 1649 ; by which plan the public saved se- enjoyment of vigorous health, may eat veral thousand pounds a year on account bread immediately after it is baked, withof post-masters. In 1657, the post-office out any sensible injury from it, but weakly was established nearly on its present foot- and aged persons cannot; and no one can

THE POST-OFFICE.

RIPE BREAD

eaten.

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