Illustration and diagram showing the apparatus ordinarily used in X-ray photography, together with the course of the electric circuits, and a radiograph of the hand.
[Large diagram] (46 kB)
![[Large diagram]](#535149607468238645_fig1527_lg.jpg.id-7853939355523447847.wrap-0.html.html){kind=link}
LIQUID AIR AND ITS MARVELS OF LOW TEMPERATURE
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| Liquid Air in water. The silvery bubblesare liquid oxygen; the nitrogen boils away. | Filtered Liquid Air in a Dewar bulb, and LiquidAir in an ordinary glass bulb (which has collected acoating of frost). |
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| Driving a nail with a hammer madeof mercury frozen by Liquid Air. | |
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| Liquid Air boiling on a block of ice, causedby the difference of temperature. | Burning steel in an ice tumbler partly filled withLiquid Air. |
| Liquid Air is simply its gaseous form brought into liquid condition by the combined effect oflowering itstemperature and subjecting it to an extreme expansion. When protected from external heat and highly exhaustedit becomes a transparent, jelly-like, mass. By means of liquid hydrogen it may be condensed into a white solidwith a faint blue tint. | |