The text begins with a concise history of electricity, tracing investigations from ancient observations of amber by Thales to Leyden jar experiments and nineteenth-century breakthroughs by Galvani, Volta, and Faraday. Having established these foundational milestones, the author emphasizes that true understanding comes from practical application in the workshop rather than abstract theory. Readers are guided through equipping a modest workspace with basic tools and building essential aids like a magnet-winding reel.
Subsequent sections detail the principles of permanent and electro-magnets, exploring magnetic lines of force and how current-carrying wires create magnetic fields. The text categorizes the three primary sources of electrical generation—frictional, voltaic or galvanic cells, and electro-magnetic induction—while explaining internal resistance, electromotive force, and units of measurement including volts, amperes, ohms, and watts.
Moving into practical applications, the book provides step-by-step instructions for constructing everyday apparatus such as switches, push buttons, electric bells, and annunciators, alongside window switches for burglar alarm systems. It covers the chemistry and maintenance of secondary batteries and accumulators, and details the operation of telegraph keys and sounders using the Morse code.
Advanced topics include high-tension apparatus, induction coils, and condensers used in early wireless telegraph systems. The author then examines acoustic and magnetic telephones, including the mechanics of microphones and automatic receiver hooks. Further chapters explore electrolysis, water purification through aluminum electrodes, and electroplating processes for coating base metals with copper or silver.
The final portions of the volume address electric heating through high-resistance wires, thermo-electricity, and the complexities of alternating currents, choking coils, and transformers. After reviewing arc and incandescent lighting systems, the author touches upon early experiments with X-rays and radium, concluding with a comprehensive index and glossary designed to reinforce the terminology introduced throughout the chapters.
