The Power of Heat and Cold


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It has often surprised us to see what an amount of clap-trap and deception there is in a name. For a great number of years heat had been employed in combination with wa ter to form—a useful agent—steam, which for a long time had driven our engines, looms, steamships, and locomotives, and has done good service, but then it was nothing but steam,- a plain old fashioned name. Well all at once there has arisen a great rival in fame to it, which has been called caloric (in com mon language heat) which no sooner has made its appearance under such a cognomen, than straightway the whole race of light H- terati—the lovers of long names; fall down and worship it, and rot only speak lightly of the services of such a faithful old servant as steam, but deny their value. We were amused in reading in one of our daily papers last week, a slap-dash article on steam and caloric in which the editor writes the epi taph of the lormer and the prologue to the reign of the latter. The caloric of the said paper was nothing more nor less than hot air —heat and air combined, and no more caloric in reality than steam is. The power of steam is developed by a che mical action, viz., simple combustion, hence we cannot obtain power from a steam engine without burning iuel. It is this application of chemical force to move machinery, which has changed the whole face of society, in respect to commerce, travel and mannufacture during the last century. It is this action which now unites far distant lands by a few days' ocean journey. The quantity of coal consumed to move a machine may then be considered the exponent of power to propel machinery. The power of a certain quantity of coal must be definite—it cannot have the property of de veloping infinite force, because the heat which is developed by the combustion of a certain quantity of coal is definite. By no plan but the hocus-pocus oi humbug (excuse the term, we would not use it only it is the best for the purpose) can it produce but a certain quantity of motion—mechanical power. There are men, however, who pretend to know something about science and logic—but they never sure ly studied philosophy nor consulted reason— who have asserted that a certain quantity of heat once developed by the combustion of a certain amount of coal, will produce an infi nite quantity of motion. They say, "heat produces motion, and when a certain quantity of it is developed in steam and then conden sed, it is annihilated and lost, but the heat of hot air is given out, taken up by wire gauze, given out again, and so on, never lost, but go ing on producing an infinite amount of force.' Their principle of logic may be thus defined mathematically. a?6=e—6=ax6=2c—6= aXi =3c, &c, a is a certain amount of heat, b is a_ certain. s.moun$ of. air, amUc the stroke of an engine. The above is absurd, and points out clearly the reasoning of the hot air philo sophers, who assert that a definite amount of heat can produce an infinite amount of motion —any number of strokes of an engine by mul tiplying and subtracting the same quantities of heat and air to and from one another alter nately. Heat produces great changes; it causes bo dies to move with great rapidity, but cold is as much the source of such a. power as heat, it produces as great changes. If the earth, sea, and air, and the whole universe were of one temperature there would be no motion.— It is the exhaustion of the hot steam and hot air into a colder medium, which makes their res pective engines move; they could not exhaust into mediums of the same temperature. How absurd then, to talk of heat being the cause of all motion in machinery. It requires both heat and cold to produce motion (by chemical forces) in machinery. Heat heaves up rocks from the depths of burning craters; cold splits rocks to pieces, and bursts hollow balls of iron into fragments. The currents of the ocean, and the whirlwinds in their wrath are not produced by heat alone, but heat and cold, they are the effects oi combined causes. These principles of mechanical philosophy as set forth, we hold to be incontrovertible; there is a philosophy falsely so called which has recently been propagated in this and oth er cities, and which we have endeavored to controvert, because we believe that the pro mulgation of any error in science and art hin ders the progress of truth and retards the march of discovery.

Scientific American Magazine Vol 8 Issue 29This article was published with the title “The Power of Heat and Cold” in Scientific American Magazine Vol. 8 No. 29 (), p. 229
doi:10.1038/scientificamerican04021853-229a

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