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.

pulse of which is converted by the air-column above into a musical sound.

Fig. 138. —Section of an ordinary wooden "flue" pipe.

In even the smallest organs more than one pipe is actuated by one key on the keyboard, for not only do pipes of different shapes give different qualities of tone, but it is found desirable to have ranks of pipes with their bottom note of different pitches. The length of an open pipe is measured from the edge of the lip to the top of the pipe; of a stopped pipe, from the lip to the top and back again. When we speak of a 16 or 8 foot rank, or stop, we mean one of which the lowest note in the rank is that produced by a 16 or 8 foot open pipe, or their stopped equivalents (8 or 4 foot). In a big organ we find 32, 16, 8, 4, and 2 foot stops, and

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