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of the Spaniards. They considered fire as a malevolent being, sent to annoy them.

The important uses of heat, and the means of procuring it for common purposes are well understood j but it has long been a desideratum to condense the quantity of heat, so as to procure from it all the effects it is capable of producing; for this purpose convex lenses and concave mirrors, of an immense magnitude have been constructed, to collect the solar rays; furnaces of various forms have been built; bellows have been added to supply a current of air. These measures are useful in various operations; but to an American belongs the honour of having constructed an apparatus from which the most astonishing effects are to be derived, and a degree of heat produced, unknown to preceding experimenters.

When we reflect how few of our literary gentlemen have been employed in chymical research, it must be regarded as an honourable trophy for American genius to have achieved this object. I shall proceed to notice the discovery alluded to, after premising a short summary of the theory of combustion.

Our atmosphere is composed chiefly of two distinct kinds of air. One hundred parts of it contain about seventy-two of air called azotic, and twenty-eight offiure air, called also vital air, Jirc air, Uc. This pure air is itself a compound body consisting of an immense quantity of heat (in a latent state*) and a certain base called oxygen. Combustion consists in the separation of these two substances, by exposing to them a third, as burning charcoal, in this case, the oxygen or base of pure air will unite with the coal, while the heat will be disengaged. The flame of the lamp which enables me to state this truth, is supported in this manner. The blaze upon my hearth exhibits a brilliant specimen of the experiment. How many thousands are there, who burn whole forests of hickory, without comprehending the process of nature by which it is effected! But to return to my subject. There exist in nature an immense variety of inflammable substances, capable of separating

• To explain what is meant by latent heat, I may just observe that two substances may be precisely equal in temperature, that is, may each raise the thermometer to the same degree, and yet one shall contain twice as much absolute, or latent heat as the other, which may be proved by decomposing it. Sec Black, Crawford, kc.

the heat from pure air. Mr. Robert Hare, junr. of this city, selected from among them two, inflammable air, and charcoal. He contrived a machine, capable of containing, in two separate compartments, a quantity of pure and inflammable airs. These were freed from all foreign mixture, and by the descent of water into the compartments, a steady constant stream of air was forced through two tubes passing from each compartment. A piece of lighted coal, was placed at the point where the air from the tubes issued by a common orifice. At this point the heat is intense and capable of producing the most astonishing effects.

Previously to the invention of this instrument, all the pure earths were considered as infusible, excepting pure clay, which was imperfectly fused by the celebrated Lavoisier. By means of the apparatus we have described, alumine, barytes, strontites, and silex were all found to be fusible perfectlt/t&nd lime and magnesia, imperfectly.

Among the metals, platinum (which has only been obtained in purity since this discovery) and also gold and silver, were not only melted, but absolutely boiled and cvaporaicd, when exposed to the heat of the compound blow-pipe.

Platinum in its native, impure, granular form, is less refractory, but had never been fused in a furnace, unless by Mr. Butland, an ingenious artist of this city, by whom it was subjected tothe combustion of a species of coal found on the banks of the Lehigh, which may from this circumstance be supposed to produce a greater heat than any coal employed in Europe. Mr. Butland deserves much credit for discovering this fact in regard to a fossil in the vicinity of Philadelphia, which will probably become at some period very useful. Certain pure specimensof platinum, which Mr. Cloud of the mint had procured, by his metallurgic skill, could not be in the least affected by the heat of Mr. Butland's furnace, they were however readily fused and volatilized by the compound blowpipe. Some of the specimens fused by Mr. Hare, at the request of Mr. Cloud, are "preserved by thisgentleman,and are found to be unusually ductile; he has preserved them in laminae of great beauty.

The apparatus we have noticed is described in a memoir published in 1802, by order of the Chymical Society of this city, and re-published in the Philosophical Magazine of London, and in the Annales dc Chimie at Paris. Some alterations have been made in it of late by Mr. Cloud, and the apparatus is exhibited at Peale's Museum, thus altered. He has omitted some parts of it, useless in his experiments, but has not improved it, or augmented its powers.

As I regard this invention of Mr. Hare as one of the most important chymical discoveries which has been made in America, and highly deserving of the most honourable mention, I have perhaps dwelt on it longer than was necessary.

The effects of heat are so constantly before us that we cease to notice them. It is the presence or absence of heat that decides the mode of existence of all bodies in nature. Are they solid? increase their temperature and they melt. Are they liquid? heat will dissipate them into vapour. These three states, solid, liquid, and oeriform, are assumed by certain substances which we daily notice. The condensation of clouds of vapour into rain, hail, and snow, affords an instance. Mercury may be exhibited as a solid, by reducing its temperature, and as a vapour by raising it. In short, we need no longer ridicule the idea of the possibility of discovering a universal solvent. Heat is the Alkahest. This we prove by all its known effects, and we can easily believe the prediction, that, " the elements shall melt with fervent heat/'

Paracelsus.

MISCELLANY FOR THE PORT FOLI<5.

I'll range the plenteous intellectual field'

And gather every thought of sovereign.powcr

To chase the moral maladies of man.—Dr. YOUNO.

Mr. Oldschool,

I am one of those who have held an opinion that the Spaniards art> an idle, slow, luxurious, and debased people, as deficient in energy as in courage; but having corrected some of my errors on this, as on other subjects relating to Spain and its inhabitants, by a better acluaintance with Spanish History, and the works of the most liberal French and English travellers through Spain, I will, with your permission, occasionally occupy a few of your pages, with such extracts and original observations, ai, I trust, will prove amusing to many of Vol. t. U

your readers, and, perhaps, dispersed few of those prejudices on this subject which have long prevailed in Europe and America. I will not attempt to enter into the region of politics, but leave the question, whether Spain is, in future, to be ruled by the Bourbon or the Napoleon Dynasty, to quidnuncs and politicians; and content myself with merely attempting to serve up an " Olla Podrida" for the entertainment of your friends. Like this favourite dish of the Spaniards, I will endeavour to have mine composed of the " choicest parts of the most nutritious viands;" and, if I fail te give satisfaction, it will not be for want of materials, but through uttskilfulness in the preparation of them, and inability to suit them to every taste.

"OLLA PODRIDA."

Idleness and slowness of the Spaniards.

The Chevalier de Bourgoanne, an enlightened French traveller, a close observer of men and manners and an elegant scholar, who visited Spain in the year 1782, and was a long time secretary to the French embassy at that court, speaking of the idleness and inactivity with which the Spaniards are generally reproached, observes—" If I have not quite absolved them from their idleness, I have taken the liberty to assert, that it was the consequence of transient circumstances, and will disappear with them. In fact, when we witness the activity which appears upon the coast of Catalonia, throughout the whole kingdom of Valencia, in the mountains of Biscay, and in all places where industry is encouraged, and commodities have an easy and certain sale; when on the other hand, we observe the laborious life of the muleteers and calessieros, who courageously conducttheir mules and carriages throughout the whole country by the most dan ■gerous roads; the husbandmen who, in the plains of La Mancha and Andalusia, harden themselves to the labours of the fields, which the nature of the soil, the distance of their habitations, and the heat of the most burning climate in Europe, render more painful than in other countries; when we consider the number of Galicians and Asturians who, like our Auvergnians and Limousins, seek at a distance the slow and painful means of subsistance; when we perceive the idleness with which the Spaniards are so much reproached, is circumscribed within the boundaries of the two Castiles, that is, the part of Spain the most unprovided with roads, canals, and navigable rivers; it is but just, to conclude, that this vice is not an indelible stain upon the Spanish nation; that it is only the result of the transient nature of things, and that a government active and enlightened might find means entirely to eradicate it."

There is another defect which has much affinity to idleness, at least it manifests itself by much the same symptoms; which is slowness; and from this it would be more difficult to exculpate the Spaniards. It must be allowed, that knowledge penetrates but slowly into Spain. In political measures, war, and all the operations of government; nay, even in the common occurrences of life, when other nations act, they deliberate. Mistrustful and circumspect, they fail in as many affairs by slowness, as others by precipitation. This is the more extraordinary, as their lively imagination should seem of a nature to be irritated by delay. But in nations, as in individuals, there is not a single quality which is not frequently modified by a contrary one, and in the struggle, the triumph is always on the side to which the mind is most forcibly disposed by the circumstance of the moment. The Spaniard naturally cold and deliberate when nothing extraordinary moves him, is inflamed to enthusiasm, when his haughtiness, resentment, or any of the passions which compose his character, are awakened either by insult or opposition. Hence it is, that the Spanish nation, apparently the most grave, cold, and slow in Europe, sometimes becomes one of the most violent when circumstances deprive it of its habitual calm and deliver it up to the empire of the imagination. The most dangerous animals are not those which are in the most continued agitation. The aspect of the lion is grave as his pace; his motions are not without an object; his roarings not in vain. As long as his inaction is undisturbed he loves peace and silence, but if he be provoked, he shakes his mane; fire sparkles in his eyes; he roars tremendously, and the king of animals appears.

It is this combination of slowness and violence which, perhaps, constitutes the most formidable courage ; and such seems to me to be that of the Spaniards.

"Our Lady of the Pillar."

It will be remembered, that in the late action between the French and Spaniards, before Zaragoza, the Spanish army was preceded by "Our Lady of the Pillar," whom the Zaragozians invoked to crown their efforts with victory. Why she should be invoked by the Zara gozians in particular, and who she is, is, perhaps, little known on this side the Atlantic. The fact is, most towns in Spain have their favou

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