nydus/How it WorksPublic

Archibald Williams explains the scientific principles behind common mechanisms and physical phenomena such as steam, electricity, light, and hydraulics. The text focuses on the fundamental operation of everyday devices rather than specific models or detailed technical specifications.

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Table of Contents

HOW IT WORKS.

practically all air has been sucked by a mercury pump before sealing.

Fig. 81. —The electrical counterpart of Fig. 80. The filament takes the place of the contraction in the pipe.

The manufacture of glow-lamps is now an important industry. One brand of lamp²⁰ is made as follows:—First, cotton-wool is dissolved in chloride of zinc, and forms a treacly solution, which is squirted through a fine nozzle into a settling solution which hardens it and makes it coil up like a very fine violin string. After being washed and dried, it is

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