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ruinous effects sometimes produced by ignorance of this subject are strikingly illustrated by the following fact :

"It is not many years since an attempt was made to establish a colliery at Bexhill, in Sussex. The appearance of thin seams and sheets of fossil wood and wood-coal, with some other indications similar to what occur in the neighbourhood of the great coal-beds in the north of England, having led to the sinking of a shaft, and the erection of machinery on a scale of vast extent, not less than eight thousand pounds are said to have been laid out on this project; which, it is almost needless to add, proved completely abortive, as every geologist would have at once declared it must, the whole assemblage of geological facts being adverse to the existence of a regular coal-bed in the Hastings' sand; while this on which Bexhill is situated is separated from the coal strata by a series of interposed beds of such enormous thickness as to render all idea of penetrating through them absurd. The history of mining speculations is full of similar cases, where a very moderate acquaintance with the usual order of nature, to say nothing of theoretical views, would have saved many a sanguine adventurer from utter ruin."*

The study of the various branches of Natural History might also be rendered productive of utility in different departments of the arts. It is quite evident that a scientific knowledge of Botany must be highly useful to gardeners and their labourers, and to all who take an interest in horticultural and rural operations. Not only a knowledge of the classification and arrangement of plants, but also of their physiological structure and functions, of their medicinal qualities, and of the chymical properties of soils and the different manures, will be found of considerable utility to such individuals. Zoology and Comparative Anatomy, which describe the peculiar structure and habits of animals, both foreign and domestic, will convey various portions of interesting information to shepherds, cattle-dealers, and agriculturists of every description. An acquaintance with Mineralogy, which treats of the solid and inanimate materials of our globe, the earthy, saline, inflammable, and metallic substances of which it is composed, must be interesting to

*Herschel's Discourse, &c.

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lapidaries, jewellers, iron-founders, and all who are employed in working various metals. To know the nature of those substances on which they are operating, the materials with which they are united in their native ores, their combination with phosphorus, sulphur, and carbon, the changes produced upon them by oxygen and the different acids, their relations to heat, and the liquids with which they may come in contact, and the various compounds into which they may be formed, will have a direct tendency, not only to increase their stock of general knowledge, but to render them more skilful and intelligent in their respective professions. Meteorology, which treats of the weather and the variable phenomena of the atmosphere, will, in many instances, be found a useful study to mariners, fishermen, travellers, and farmers, by which they may frequently be directed in their movements, and avoid many inconveniences and dangers. By carefully attending to the motions of the barometer and thermometer, and comparing them with the electrical state of the atmosphere, the direction of the winds, and the appearances of the clouds, the farmer may be warned of the continuance of rain or drought, and direct his operations accordingly, so as to protect his produce from danger.

There is no application of science to the arts of more importance, and more extensive in its effects, than that of the employment of steam for driving all kinds of machinery, and for propelling vessels along rivers and across the ocean. "It has armed," says Mr. Jeffrey, "the feeble hand of man with a power to which no limits can be assigned-completed the dominion of mind over the most refractory qualities of matter, and laid a sure foundation for all those future miracles of mechanic power which are to aid and reward the labours of after generations." The first person who appears to have entertained the idea of employing steam for propelling vessels was Mr. J. Hulls, in the year 1736. But it was not till 1807, when Mr. Fulton launched, at New-York, the first steamboat he had constructed, that navigation by steam was introduced to general practice, which may therefore be considered as the epoch of the invention. In a few years every river and bay in the United States became the scene of steam navigation. In 1822 there were more than 350 steam-vessels connected with these States, some of them of eight and nine hundred tons burden, and by this time,

doubtless, they are more than doubled. In 1819 an expedition left Pittsburg, descended the Ohio in steamboats for 1100 miles, and then, ascending the rapid Missouri, proceeded to the distance of no less than two thousand five hundred miles. They have now been introduced into every country in Europe. On the principal rivers and seas connected with the British isles, and even in the Scottish lakes, these vessels are sweeping along in majestic pomp, against wind and tide, diversifying the scenery through which they pass, and transporting travellers and parties of pleasure to their destination, with a rapidity unexampled in former ages. On the Clyde alone more than fifty or sixty steam-vessels are constantly plying. The scenery of the Rhine, the Rhone, the Elbe, the Seine, the Danube, the Wolga, the lakes of Constance and Geneva, and of many other rivers and inland seas, is now enlivened by these powerful machines, conveying goods and passengers in every direction. Even the Atlantic Ocean, an extent of more than three thousand miles, has been traversed by a steamboat in twenty days; and the period, we trust, is not far distant, when the Red Sea, the Persian Gulf, the Bay of Bengal, the Indian Ocean, the Mediterranean, the Euxine, the Gulf of Mexico, and even the wide Pacific, will be traversed by these rapid vehicles, conveying riches, liberty, religion, and intelligence to the islands of the ocean, and forming a bond of union among all nations.

The admirable improvements in the construction of steamcarriages which are now going forward are no less worthy of attention. The rapid movements of these machines, which have been lately introduced on the Liverpool and Manchester railway, and the security and comfort with which they are attended, have excited the astonishment of every beholder. And no wonder, since goods and passengers are now conveyed between these cities with a velocity of nearly thirty miles an hour! so that it may be said, with the strictest propriety, that the steam-engine is the most brilliant present ever made by philosophy to mankind.

The discovery of carburetted hydrogen gas, and its application to the purpose of illuminating our dwelling-houses, streets, and manufactories, may also be considered in reference to the arts. Every city, and every town of a moderate size, is now enlivened with the splendid brilliancy produced

from this invisible substance; pipes for its conveyance have been laid, of many hundred miles in extent, and diverging into numerous ramifications, and thousands of artists are employed in conducting its manufacture, and forming tubes and other devices for distributing it in all directions.

Now, since the inventions to which I am adverting are founded on chymical and mechanical principles, and on the discoveries of modern science, and since many thousands of mechanics are now employed in constructing the machinery connected with these inventions, and in conducting its operations both by sea and land, it is of the utmost importance, in order to their being fully qualified for their respective departments, that they understand the scientific principles which enter into the construction of such machines and engines, the peculiar uses of every part, the manner in which the chymical agents employed operate, and the effects which, in any given circumstance, they must necessarily produce. In particular, it is indispensably necessary, that engine-men, and others employed for directing these machines when in operation, should be acquainted with every part of their structure, and the principles on which their movements depend; for the comfort and safety of the public are dependent on the caution and skill with which they are conducted. How could any man be qualified for such an office without some portion of scientific knowledge? and how could travellers in such vehicles consider their lives and property secure, if they were not guided by men of intelligence and prudence? To the want of such caution and skill are chiefly to be attributed most of the disasters and fatal accidents, connected with such operations, which have hitherto taken place.

Besides the agriculturists, manufacturers, mechanics, and artificers alluded to above, there are numerous other classes to which similar remarks will apply. In short, there is scarcely an individual, however obscure, in any department of society, but may derive practical benefit from an acquaintance with science. "The farm servant or day labourer," says Lord Brougham, "whether in his master's employ or tending the concerns of his own cottage, must derive great practical benefit,-must be both a better servant, and a more thrifty and, therefore, comfortable cottager, for knowing something of the nature of soils and manures,

which chymistry teaches, and something of the habits of animals, and the qualities and growth of plants, which he learns from natural history and chymistry together. In truth, though a man is neither a mechanic nor a peasant, but only one having a pot to boil, he is sure to learn from science lessons which will enable him to cook his morsel better, save his fuel, and both vary his dish and improve it. The art of good and cheap cookery is intimately connected with the principles of chymical philosophy, and has received much, and will yet receive more, improvement from their application." Nay, even the kitchen maid, the laundry maid, and the mistress of every family, may derive many useful hints from the researches of science. The whole art of cookery is a chymical operation, and so are the arts of washing, dressing, bleaching, and dying. By a knowledge of the nature and properties of the acids and other chymical substances, they would learn how to eradicate stains of ink, grease, &c. from cotton, linen, woollen, and silks, in the safest and most effectual manner, and many other processes of great utility in domestic life. Even the art of kindling a fire, and of stirring it when kindled, depends on philosophical principles. For example, the stirring of a fire is of use, because it makes a hollow, where the air being rarefied by the adjacent heat, the surrounding air rushes into the partial vacuum, and imparting its oxygen, gives life to the fire, and carries the flame along with it. On this principle the following rules are founded:1. Never stir a fire when fresh coals are laid on, particularly when they are very small, because they immediately fall into the vacuum, and prevent the access of the oxygen of the atmosphere, which is the principle of combustion. 2. Always keep the bottom bar clear, because it is there chiefly that the air rushes in to nourish the fuel. 3. Never begin to stir at top, unless when the bottom is quite clear, and the top only wants breaking, otherwise the unkindled fuel may be pressed down in a body to the bottom, and the access of atmospheric air prevented.

Illustrations, of a similar kind, of the practical applica tions of science, might have been given to an almost indefinite extent; but the above specimens may suffice as corroborative of the general position-that scientific knowledge would render mechanics and manufacturers of all descrip

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