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"Radio was as much the culmination of the work of a series of scientists in the 19th Century, starting with Faraday, as it was an invention by Marconi. This book aims to illustrate the contributions made by these scientists and show how each was dependent upon the work and ideas of his predecessors; Faraday, Henry, Maxwell, Hughes, Fitzgerald, Hertz, Lodge and Marconi. The book represents the result of a long period of study by a man who knew the story well and researched it thoroughly; although Gerald Garratt died in 1989 the manuscript has been completed by his daughter.Gerald Garratt had a special interest in what might be termed the "pre-history" of radio. His book therefore outlines the sequence of development from Faraday's first prediction and concept of the electromagnetic field, the mathematical definition of the conditions for propagation of waves by Maxwell, the demonstration of their physical existence by Hertz, identification of the need for resonance between transmitter and receiver by Lodge and finally Marconi's successful practical application and "invention"."

"This book examines the discourse surrounding the wireless, created by the Anglo-Italian inventor Guglielmo Marconi. This book establishes a broader definition for technical communication by examining a selection of the discourse surrounding Marconi's wireless. The book?s main themes are the following : (1) technical communication is all discourse surrounding technology, (2) the field of technical communication (or technical writing) should incorporate analyses of discourse surrounding technologies into its epistemology, (3) the wireless is a product of the society from which it comes (early twentieth-century Western civilization), and (4) the discourse surrounding the wireless is infused with tropes of progress, speed, efficiency, evolution, and ahistoricity."

"An unpolarized light beam will change to a linear polarized beam by using a polarizing filter. In turn the linear polarized beam can be rotated in an active medium such as glass if a magnetic field exists. This phenomenon, which is known as Faraday effect, is there for can used as a current sensor. In this experiment, the current to be measured was flowed in Helmohltz coils where a homogeneous magnetic field was generated. Bismuth and Flumbo alloys were used as glass medium. An analyzer detected the linear polarized beam came from the glass. The analyzer was adjustable and has a capability to detect a light signal up to 1 mill radian per degree. The values of the rotation of the polarized light beams in the active medium were determined by Verdet's constant. The characteristics of the glasses were represented by plotted curves of rotation angle versus the wavelengths of the light beam, which shows parabolic form. The sensing current by Faraday effect shows a linear feature of rotation angle with respects to the current value, as predicted by the theory. The result also shows that the glass of Bismuth alloy is more sensitive than the Plumbo alloy."