Meteorological Observations and Essays |
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active altitude AMANUENSIS angle April April 25 arch atmosphere aurora borealis barometer beams appear betwixt bright centre circle circumstance clouds cold column condensed conjectures cubic foot cylinder decrease density distance dry air earth's magnetism earth's surface elastic fluid elevation equal essay evaporation extreme fact faint frost Gosport greater height hemisphere hence higher hoar frost horizon horizontal light hygrometer inches inches of mercury intersection January July June June 12 Kendal and Keswick latitude luminous magnetic effluvia magnetic meridian March Mean high mean temperature mercury meteors miles months mountains nearly needle object observations October parallel past full pear gauge perpendicular phenomena Philosophical Transactions plane pole PROPOSITION quantity rain rarefaction Scholium season seen Skiddaw snow stratum streamers supposed theodolite thermometer thunder tions torrid zone trade winds vapour variation winds winter yards zenith
Popular passages
Page 152 - SHERER and Ross and myself were admiring the extreme beauty of this phenomenon, from the observatory, we all simultaneously uttered an exclamation of surprise at seeing a bright ray of the aurora shoot suddenly downward from the general mass of light, and between us and the land, which was there distant only three thousand yards.
Page 57 - Every one gazed with astonishment, but the uncommon grandeur of the scene only lasted one minute ; the variety of colours disappeared, and the beams lost their lateral motion, and were converted into the flashing radiations.
Page 125 - ... fluid partaking of the properties of iron, or rather of magnetic steel ; and that this fluid, doubtless from its magnetic property, assumes the form of cylindrical beams.
Page 141 - In summer, after a long continuance of fair weather, with the barometer high, it generally falls gradually, and for one, two, or more days, before there is much appearance of rain. — If the fall be sudden and great for the season, it will probably be followed by thunder.
Page 78 - ... country varies according to the barometer, or otherwise that the height is little affected therewith, and that the whole or greatest part of the variation is occasioned by a change in the density of the lower regions of the air. It is very improbable that the height of the atmosphere should be subject to such fluctuations, or that it should be regulated in any other manner than by the weekly or monthly mean temperature of the lower regions; because the mean weight of the air is so nearly the...
Page 113 - As this essay contains an original discovery which seems to open a new field of inquiry in philosophy, or rather, perhaps, to extend the bounds of one that has been, as yet, but just opened, it may not, perhaps, be unacceptable to many readers to state briefly the train of circumstances which led the author to the important conclusions contained in the following pages.
Page 152 - ... yards. Had I witnessed this phenomenon by myself, I should have been disposed to receive, with caution, the evidence even of my own senses, as to this last fact ; but the appearance conveying precisely the same idea to three individuals at once, all intently engaged in looking towards the spot, I have no doubt that the ray of light actually passed within that distance of us.
Page 113 - The inference, therefore, was unavoidable that the beams were guided not by gravity, but by the earth's ' magnetism ' and the disturbance of the needle that had been heretofore observed during the time of an aurora seemed to put the conclusion past doubt.
Page 57 - At half-past ten o'clock streamers appeared, very low in the south-east, running to and fro from west to east ; they increased in number, and began to approach the zenith apparently with an accelerated velocity ; when all on a sudden the whole hemisphere was covered with...
Page 154 - Mr. Ellicott, at sea, off Cape Florida, was another spectator. "I was called up," he states, " about three o'clock in the morning to see the shooting stars, as they are called. The phenomenon was grand and awful. The whole heavens appeared as if illuminated with sky-rockets, which disappeared only by the light of the sun toward daybreak.