TRANSFER OF ATMOSPHERIC HEAT. 21 commerce, and suspend the occupation of many of our people. The general excellence of our cattle and flocks; the abundance of winter feed, and the state of vegetation, and the multitude of fine and useful products, all speak in favour and in commendation of our climate. God's bountiful care, What tongue can recite; It descends to the plain; In the dew and the rain. Frail children of dust, And feeble as frail; In thee do we trust, Nor find thee to fail. Thy mercies how tender, GRANT. The propositions of the transfer of atmospheric heat is one of the most important properties of that great agent of nature. It conveys the idea of the independent and inherent power of heat, and its attribute of motion. It is the great locomotive agent and power of nature. It urges forward the railway train surmounted by its trailing and graceful plume of steam, and it causes those mighty and majestic winds that sweep along at the rate of 50 and 60 miles an hour, bearing on their wings a canopy of clouds of steam, raised 22 LOCOMOTIVE POWER OF HEAT AND TRANSFER. eve. from the great abyss of waters, or it plays in those gentle zephyrs that sigh so softly on the summer's Thus heat-with steam and pressure-produce all the motions of the atmosphere, and from the transfer of heat all motion is derived, because it must move first in order to put other things in motion. It is the prime mover. The air of a room may be cold, quiescent, and stagnant; light the gentlest spark of fire, and motion begins; the fire draws the air it quickens, and a draught or current of the whole is soon established. What the fire does to the room, the glorious sun does to the earth and atmosphere. For the present we must receive the fact of the transfer of heat as a simple proposition which will hereafter come under full consideration. Heat, then, is as a spirit that has wings of its own and flies away by itself through the air. The doctrine of the transfer of the atmospheric heat, if accepted to its full extent, leads to the selfevident conclusion, that there is only a definite amount of heat-a constant and unvarying quantity-and in adopting this principle we only associate heat with electricity, for it is a fundamental law, that no one body can become charged with a greater amount of electricity, unless some other body has lost that quantity. Hence the law of definite quantity applies equally to heat and electricity, and connects them with the definite proportions and chemical equivalents of matter, which are the basis and the perfection of modern chemistry. CHAPTER II. Inducements to the Study of Meteorology-as a Field of Intellectual Research -and Pleasureable Pursuit-and from the Variety and Beauty of its Picturesque Scenery.-Epitome of the year 1814 from Howard's Tables.Analysis of the Epitome-and the Evidence of a Majority of Recurring Days of Highest and Lowest Barometer and Thermometer-showing the tendency to a Periodic Action.-The Consecutive Series or the Order of Time in which the Different States-or the Cardinal Points of the Months occurred, exhibiting the Discrepancies between the Barometer and Thermometer.-Observations and Remarks relative to the differences and irregularities of the Instruments-and their want of Concord-which, like the motions of the Heavenly Bodies, is more apparent than real.-The Upper and Lower Regions of the Atmosphere exhibit frequently diverse states of Temperature.-Milton's idea of the Magnetic Powers of the Sun's rays confirmed by Professor Faraday's Researches on the Magnetic Conditions of the Atmosphere-and the Sun's action on the Needle.— Explanation of the Discrepancies by Strata or Beds of Air of equal volumes of unequal Temperatures and varying Densities.-A System of Compensation whereby the volume or measure of the Atmosphere is maintained under varying states of Pressure.-The Tropics.-the Temperate and Polar Regions have specific actions and characters in respect to the Atmosphere.-List of celebrated Frost Fairs on the Thames.-The last great Frost Fair of 1814-Detailed account of.-Severity of the Winter of 1814 in the North of Europe. 22 LOCOMOTIVE POWER OF HEAT AND TRANSFER. from the great abyss of waters, or it plays in those gentle zephyrs that sigh so softly on the summer's eve. Thus heat-with steam and pressure-produce all the motions of the atmosphere, and from the transfer of heat all motion is derived, because it must move first in order to put other things in motion. It is the prime mover. The air of a room may be cold, quiescent, and stagnant; light the gentlest spark of fire, and motion begins; the fire draws the air it quickens, and a draught or current of the whole is soon established. What the fire does to the room, the glorious sun does to the earth and atmosphere. For the present we must receive the fact of the transfer of heat as a simple proposition which will hereafter come under full consideration. Heat, then, is as a spirit that has wings of its own and flies away by itself through the air. The doctrine of the transfer of the atmospheric heat, if accepted to its full extent, leads to the selfevident conclusion, that there is only a definite amount of heat-a constant and unvarying quantity-and in adopting this principle we only associate heat with electricity, for it is a fundamental law, that no one body can become charged with a greater amount of electricity, unless some other body has lost that quantity. Hence the law of definite quantity applies equally to heat and electricity, and connects them with the definite proportions and chemical equivalents of matter which are the basis and the perfection of modern chemistry. |