 | Royal Society (Great Britain) - 1865 - 636 pages
...placed at the dark focus, is instantly ignited. 6. Disks of charred paper placed in the focus are raised to brilliant incandescence, surfaces of considerable...focus by the ignition of its envelope. 9. A piece of zinc foil, blackened on one side to diminish reflexion, is pierced and inflamed. By gradually drawing... | |
 | Royal Society (Great Britain) - 1865 - 634 pages
...ignited. 7. A piece of charcoal, suspended in a receiver of oxygen, is ignited in the dark focus aud caused to burn brilliantly, the rays after crossing...focus by the ignition of its envelope. 9. A piece of zinc foil, blackened ' on one side to diminish reflexion, is pierced and inflamed. By gradually drawing... | |
 | James Samuelson, William Crookes - 1865 - 874 pages
...charcoal suspended in a receiver of oxygen is ignited in the dark focus and caused to burn brilliantly. A mixture of oxygen and hydrogen is exploded in the dark focus by the ignition of its envelope. Magnesium wire presented suitably to the focus, burns with its intensely luminous flame. In all these... | |
 | 1865 - 388 pages
...passed through the receiver, still retain sufficient power to render the charcoal within it red-hot. A mixture of oxygen and hydrogen is exploded in the dark focus, through the ignition of its envelop. A strip of blackened zinc-foil placed at the focus is pierced... | |
 | 1865 - 1144 pages
...passed through the receiver, still retain sufficient power to render the charcoal within it red-hot. A mixture of oxygen and hydrogen is exploded in the dark focus, through the ignition of its envelope. A strip of blackened zinc-foil placed at the focus is pierced... | |
 | John Henry Pepper - 1869 - 722 pages
...passed through the receiver, still retain sufficient power to render the charcoal within it red hot " A mixture of oxygen and hydrogen is exploded in the dark focus, through the ignition of its envelope. " A strip of blackened zinc-foil placed at the focus is pierced... | |
 | 1865 - 372 pages
...passed through the receiver, still retain sufficient power to render the charcoal within it red-hot. A mixture of oxygen and hydrogen is exploded in the dark focus, through the ignition of its envelop. A strip of blackened ziuc-ibil placed at the focus is pierced... | |
 | John Henry Pepper - 1877 - 764 pages
...passed through the receiver, still retain sufficient power to render the charcoal within it red hot " A mixture of oxygen and hydrogen is exploded in the dark focus, through the ignition of its envelope. " A strip of blackened zinc-foil placed at the focus is pierced... | |
 | Royal Institution of Great Britain - 1866 - 742 pages
...parsed through the receiver, still retain sufficient power to render the charcoal within it red-hot. A mixture of oxygen and hydrogen is exploded in the dark focus, through the ignition of its envelope. A strip of blackened zinc-foil placed at the focus is pierced... | |
 | 1865 - 576 pages
...at the dark focus, is instantly igniied. 6. Disks of charred paper, placed in the focus, are raised to brilliant incandescence, surfaces of considerable...be kept blazing for a considerable length of time. This is a particularly beautiful experiment. 10. Magnesium wire, presented suitably to the focus, burns... | |
| |
A strip of blackened zinc-foil placed at the focus is pierced and inflamed by the invisible rays. By gradually drawing the strip through the focus, it may be kept blazing with its characteristic purple light for a considerable time. This experiment is... 
