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acetate altitude ammonia animal Annals of Philosophy antimony appears Aquarii ARTICLE ascertain atmosphere atoms of oxygen azote barometer barytes base body boracic acid calculated carbonate carbonic acid chloride colour column combination compound contain copper correction crystals Daud density diluvial diluvium dissolved distinct dorsal dry air equal experiments feet femoral pores fluoboric acid fluoric acid genera genus grains Gray Head shielded heat hydracid hydrogen hydrogen gas inches iron latitude latter Laur Leach lime liquid magnetic pole mean mercury Merrem metallic muriatic acid nearly º º observed obtained operculum oxide oxygen paper plates portion potash pressure produced proportion quantity ratio salt saturated scales scaly selenium seleniuret shell ship silica silicium soda solution species specific gravity specimens strata substance sulphate sulphuret sulphuric acid surface teeth temperature thermometers tion toes tube valves vapour variation volume zinc
Page 51 - ... of a grain, it will be counterpoised by one of the small gold weights placed at the first, or second, or third, or fourth division. If on the contrary it weigh one grain and a fraction, it will be counterpoised by the heavy gold weight at the extremity, and one or more of the lighter ones placed in some other part of the beam.
Page 50 - The fulcrum is a bit of plate brass, the middle of which lies flat on my table when I use the balance, and the two ends are bent up to a right angle so as to stand upright. These two ends are ground at the same time on a flat hone, that the extreme surfaces of them may be in the same plane ; and their distance is such that the needle when laid across them rests on them at a small distance from the sides of the beam.
Page 51 - ... with the tension of that weight round a thicker brass wire in a close spiral, after which the extremity of the spiral being tied hard with waxed thread, I put the covered wire in a vice, and applying a sharp knife which is struck...
Page 397 - Typographia : An Historical Sketch of the origin and progress of the art of printing ; with practical directions for conducting- every department in an office, with a description of stereotype and lithography.
Page 458 - CHRISTIE having been led to doubt the validity of the moving easterly variation adopted by Canton, but, at the same time, having observed that the changes in direction and intensity appear always to have reference to the position of the sun, with regard to the magnetic meridian, was led to connect these phenomena with Professor...
Page 449 - ... fact is proved, by holding a taper or a piece of burning phosphorus within a large flame, made by the combustion of alcohol, the flame of the candle or of the phosphorus will appear in the centre of the other flame, proving that there is oxygen, even in its interior part...
Page 397 - MATHEMATICS FOR PRACTICAL MEN: Being a Common-Place Book of Principles, Theorems, Rules, and Tables, in various departments of Pure and Mixed Mathematics, with their Applications ; especially to the pursuits of Surveyors, Architects, Mechanics, and Civil Engineers, with numerous Engravings.
Page 222 - A short Account of some Observations made with Chronometers, in two Expeditions sent out by the Admiralty, at the recommendation of the Board of Longitude, for ascertaining the Longitude of Madeira and ofFalmouth.
Page 461 - ... 3. From a temperature of about 80°, the intensity decreases very rapidly as the temperature increases, so that if, up to this temperature, the differences of the decrements are nearly constant, beyond that temperature the differences of the decrements aho increase.
Page 185 - February 10, 1825, between the hours of twelve and one o'clock, as nearly as recollected, I heard an explosion, as I supposed, of a cannon, but somewhat sharper. I immediately advanced with a quick step about twenty paces, when my attention was arrested by a buzzing noise, resembling that of a humming bee, which increased to a much louder sound, something like a spinning-wheel, or a chimney on fire, and seemed directly over my head, and in a short time I heard something fall. The time which elapsed...