The Collected Works of Sir Humphry Davy ...: Discourses delivered before the Royal society. Elements of agricultural chemistry, pt. ISmith, Elder and Company, 1840 |
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aberration of light afforded albumen alburnum alcohol alkali alumina amongst animal appears applied Astronomer Astronomer Royal atmosphere azote Ballybofey bark bodies carbonic acid carbonic acid gas Cavendish chemical chemistry combined common compounds considered contain COPLEY MEDAL decomposed discovery Ditto earth elastic fluid evaporation exist experiments extract fixed stars flowers gluten grain heat Herschel honour hydrogen important inquiry iron juice knowledge labours leaves Lecture likewise lime limestone magnetic manure medal ments metallic motion mountains mucilage nature nitric acid nourishment number representing objects observations organs oxide oxygen paper parallax peculiar phenomena philosophical plants powers Priestley principles probably procured produced properties proportions quantity Ramelton rendered resin rocks Royal Society saccharine schist scientific seeds siliceous soil soluble solution species specific gravity stances starch sugar sulphuric tains tannin temperature tion trees vegetable matter vegetable substances views volatile oils wheat wood woody fibre
Popular passages
Page 130 - During the last summer also, a friend of mine gave some account of them to M. Lavoisier, as well as of the conclusion drawn from them, that dephlogisticated air is only water deprived of phlogiston ; but at that time so far was M. Lavoisier from thinking any such opinion warranted, that, till he was prevailed upon to repeat the experiment himself, he found some difficulty in believing that nearly the whole of the two airs could be converted into water.
Page 300 - Soils, when collected, if they cannot be immediately examined, should be preserved in phials quite filled with them, and closed with ground glass stoppers. The quantity of soil most convenient for a perfect analysis is from two to four hundred grains. It should be collected in dry weather, and exposed to the atmosphere till it becomes dry to the touch. The specific gravity of a soil...
Page 174 - Agricultural chemistry has for its objects all those changes in the arrangements of matter connected with the growth and nourishment of plants ; the comparative values of their produce as food ; the constitution of soils ; the manner in which lands are enriched by manure, or rendered fertile by the different processes of cultivation.
Page 93 - Mr. Dalton's permanent reputation will rest upon his having discovered a simple principle universally applicable to the facts of chemistry, in fixing the proportions in which bodies combine, and thus laying the foundation for future labours respecting the sublime and transcendental parts of the science of corpuscular motion. His merits in this respect resemble those of Kepler in astronomy.
Page 314 - Nothing can be more evident than that the genial heat of the soil, particularly in spring, must be of the highest importance to the rising plant; and when the leaves are fully developed, the ground is shaded, and any injurious influence, which in the summer might be expected from too great a heat, entirely prevented : so that the temperature of the surface, when bare, and exposed to the rays of the sun, affords at least one indication of the degrees of its fertility; and the thermometer may be sometimes...
Page 39 - ... feeling of admiration must we consider those grand monuments of nature which mark the revolutions of the Globe ; continents broken into islands ; one land produced, another destroyed ; the bottom of the ocean become a fertile soil ; whole races of animals extinct, and the bones and...
Page 135 - Cavendish was a great man, with extraordinary singularities. His voice was squeaking, his manner nervous, he was afraid of strangers, and seemed, when embarrassed, even to articulate with difficulty. He wore the costume of our grandfathers ; was enormously rich, but made no use of his wealth. He gave me once some bits of platinum for my experiments, and came to see my results on the decomposition of the alkalis, and seemed to take an interest in them ; but he encouraged no intimacy with any one....
Page 84 - Fortunately science, like that nature to which it belongs, is neither limited by time nor space. It belongs to the world, and is of no country and no age.
Page 314 - I found that a rich black mould, which contained nearly 4 of vegetable matter, had its temperature increased in an hour from 65° to 88° by exposure to sunshine ; whilst a chalk soil was heated only to 69° under the same circumstances. But the mould, removed into the shade, where the temperature was 62°, lost, in half an hour, 15° ; whereas the chalk, under the same circumstances, had lost only 4°.
Page 132 - ... state, and without having been able to bring them to the test of such experiments as would confirm or refute them; and should therefore have delayed the publication of them until these experiments had been made, if you, sir, and some other of my philosophical friends had not thought them...