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VACUUM-CLEANER, an appliance for removing dust from carpets, curtains, &c., by suction, and consisting essentially of some form of air-pump drawing air through a nozzle which is passed over the material that has to be cleaned. The dust is carried away with the ...

... es. According to circumstances, the colour of the light obtained from a PlUcker vacuum tube changes " from red to a rich steel blue," to use the words of Crookes, who first described the phenomenon. A third spectrum is distinguished by J. M. Eder and Edward Va ...

... most suitable material for an incandescent lamp was carbon contained in a good vacuum, and St G. Lane Fox and Sir J. W. Swan in England, and T. A. Edison in the United States, were engaged in struggling with the difficulties of producing a suitable carbon inc ...

... avy showed that two pieces of ice could be melted by rubbing them together in a vacuum, although everything surrounding them was at a temperature below the freezing point. He did not, however, infer that since the heat could not have been supplied by the ice, ...

... he train. FlG. 48. — Tellurium- Hence the coherer type of detectors are bismuth Vacuum Ther- called potential detectors whilst the mal Detector for Elec- thermal are called integral current detrie Oscillations, a b tectors, the current detectors depending cons ...

... ovided that the child had reached the age of four years. Finally, the VACHEROT— VACUUM TUBE public vaccinator was now required to visit the homes of children for the purpose of offering vaccination with glycerinated calf lymph, " or such other lymph as may be ...

... to consist essentially in the careful distillation of selected crude petroleum, vacuum-stills being used to minimize dissociation, and filtration of the residue through granular animal charcoal. The filters are either steamjacketed, or are placed in rooms heat ...