The Collected Works of Sir Humphry Davy: Bakerian lectures, and miscellaneous papers from 1806 to 1815

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Johnson Reprint Corporation, 1840

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Sida 63 - Nothing tends so much to the advancement of knowledge as the application of a new instrument. The native intellectual powers of man in different times are not so much the causes of the different success of their labours as the peculiar nature of the means and artificial resources in their possession.
Sida 88 - Potasium and Sodium are the names by which I have ventured to call the two new substances : and whatever changes of theory, with regard to the composition of bodies, may hereafter take place, these terms can scarcely express an error ; for they may be considered as implying simply the metals produced from potash and soda. I have consulted with many of the most eminent scientific persons in this country, upon the methods of derivation, and the one I have adopted has been the one most generally approved.
Sida 65 - When the substances were strongly heated, confined in given portions of oxygen, a rapid combustion with a brilliant white flame was produced, and the metallic globules were found converted into a white and solid mass, which in the case of the substance from potash was found to be potash, and in the case of that from soda, soda.
Sida 64 - ... this was the case. When solid potash, or soda in its conducting state, was included in glass tubes furnished with electrified platina wires, the new substances were generated at the negative surfaces ; the gas given out at the other surface proved by the most delicate examination to be pure oxygene ; and unless an excess of water was present, no gas was evolved from the negative surface.
Sida 24 - Solution of sulphate of potash was placed in contact with the negatively electrified point, pure water was placed in contact with the positively electrified point, and a weak solution of ammonia was made the middle link of the conducting chain ; so that no sulphuric acid could pass to the positive point in the distilled water, without passing through the solution of ammonia. The...
Sida 131 - Mercury by combination with about -nrtmv part of its weight of new matter is rendered a solid, yet has its specific gravity diminished from 13.5 to less than 3, and it retains all its metallic characters ; its colour, lustre, opacity, and conducting powers remaining unimpaired.
Sida 126 - Ammoniacal gas, equal to one and a half or one and three-fifths of the volume of the amalgam is found to be produced, and a quantity of oxygen equal to one-seventh, or one-eighth of the ammonia disappears.• When thrown into muriatic acid gas, it instantly becomes coated with muriate of ammonia, and a small quantity of hydrogen is disengaged. In sulphuric acid it becomes coated with sulphate of ammonia and sulphur. I attempted by a variety of modes to preserve this amalgam. I had hoped by submitting...
Sida 339 - I have found by several experiments that this is not the case. The solution of oxymuriatic gas in water freezes more readily than pure water, but the pure gas dried by muriate of lime undergoes no change whatever, at a temperature of 40 below 0° of Fahrenheit. The mistake seems to have arisen from the exposure of the gas to cold in bottles containing moisture...
Sida 77 - T'-th of an inch in diameter is easily spread over a surface of a quarter of an inch,* and this property does not diminish when it is cooled to 32° FAHRENHEIT. It conducts electricity and heat in a similar manner to the .basis of potash ; and small globules of it inflame by the voltaic electrical spark, and burn with bright explosions.
Sida 56 - Natural electricity has hitherto been little investigated, except in the case of its evident and powerful concentration in the atmosphere. Its slow and silent operations in every part of the surface...

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