 | 1771 - 428 páginas
...and keep the copper in a state of fusion for twenty minutes or half an hour, at the end of which time it will be found at the bottom of the crucible perfectly pure. The quantity of copper scales must vary in proportion to the supposed impurity of the copper to be... | |
 | 1841 - 488 páginas
...covered crucible, and keep the copper in a state of fusion for twenty minutes, at the end of which time it will be found at the bottom of the crucible perfectly pure. The quantity of copper scales must vary in proportion to the supposed impurity of the copper to be... | |
 | Perry Fairfax Nursey - 1839 - 514 páginas
...and keep the copper in a state of fusion for twenty minutes or half an hour, at the end of which time it will be found at the bottom of the crucible, perfectly pure. The quantity of copper scales must vary in proportion to the supposed impurity of the copper to be... | |
 | 1839 - 512 páginas
...and keep the copper in a state of fusion for twenty minutes or half an hour, at the end of which time it will be found at the bottom of the crucible, perfectly pure. The quantity of copper scales must vary in proportion to the supposed impurity of the copper to be... | |
 | 1840 - 812 páginas
...and keep the copper in a state of fusion for twenty minutes or half an hour, at the end of which time it will be found at the bottom of the crucible perfectly pure. The quantity of copper scales muet vary in proportion to the supposed impurity of the copper to be... | |
 | 1840 - 416 páginas
...and keep the copper in a state of fusion for twenty minutes or half an hour, at the end of which time it will be found at the bottom of the crucible perfectly pure. The quantity of copper scales must vary in proportion to the supposed impurity of the copper to be... | |
 | 1840 - 316 páginas
...and keep the copper in a state of fusion for twenty minutes or half an hour, at the end of which time it will be found at the bottom of the crucible, perfectly pure. The quantity of copper scales must vary in proportion to the supposed impurity of the copper to be... | |
 | Andrew Ure - 1856 - 1140 páginas
...Mr. Lewis Thompson, who received a gold medal from the Society of Arts for this invention, says, that after the copper has been kept in fusion for half an hour, it Till be found at the bottom of the crucible perfectly pure ; while the iron, lead, arsenic, it, with... | |
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Ground bottle glass, or any other flux 10 parts ; heat the whole together in a covered crucible, and keep the copper in a state of fusion for twenty minutes or half an hour, at the end of which time it will be found at the bottom of the crucible, perfectly... 