Charles Nordmann, an astronomer at the Paris Observatory, sets out in this 1922 work to explain Einstein's theories without a single mathematical formula. The preface by Viscount Haldane immediately signals a distinctive approach: Haldane argues that ordinary language, carefully used, can do some of the work of mathematical symbolism, and he praises the French gift for lucid expression. Nordmann's own voice, as seen in Chapter V, is direct and metaphor-rich—he calls gravitation a 'steep-cliffed island in the sea of phenomena' that Einstein annexed to his mechanics. The book is structured to move from special to general relativity, with each chapter building on the last.

Haldane's Preface as a Reading Lens

Viscount Haldane's preface is more than a commendation; it frames the entire exposition. He notes that mathematical methods offer precision but risk taking symbols as 'exhaustively descriptive of reality,' a tendency that ordinary language can correct. This sets up Nordmann's task: to translate abstract physics into French clarity. Haldane also remarks that neither English nor German writers have fully succeeded in this, implying that Nordmann's Latin heritage gives him an advantage. As you read, watch how Nordmann balances technical accuracy with metaphor—for instance, calling the principle of inertia 'nearly true' and illustrating it with a fly-wheel. The preface thus primes you to expect a work that values verbal precision over symbolic shorthand.

The Island of Gravitation

In Chapter V, Nordmann describes special relativity as passing by gravitation 'taking no notice of it,' leaving it a 'steep-cliffed island.' This image recurs: gravitation is isolated, unrelated to the rest of physics. Nordmann then explains how Einstein drew it from 'splendid isolation' and annexed it to his mechanics. The language is martial—'docile and vanquished'—and the chapter title promises to reveal how light from stars is weighed. Notice the structure: Nordmann first states the problem (gravitation as an anomaly), then the solution (general relativity), and finally the method (avoiding 'barbed wire of mathematical terminology'). This pattern of problem-solution-method appears throughout the book, guiding the reader through complex ideas.

Analogies from Everyday Experience

Nordmann grounds abstract concepts in concrete examples. To explain the principle of inertia, he describes a steam-engine's fly-wheel: 'When the engine experiences a sudden and sharp check, or an acceleration, the fly-wheel serves to keep it steady.' This is not a mere illustration; it is an argument that the principle is 'based upon experience.' Similarly, he invokes Jules Verne's projectile to discuss accelerated movement and gravitation. These analogies are not decorative—they are the core of his explanatory method. As you read, note how each analogy is introduced, developed, and then linked to the mathematical idea it represents. The fly-wheel example, for instance, leads directly to the statement that inertia is 'nearly true,' a crucial nuance for relativity.

The Rhythm of Synthesis

Nordmann repeatedly emphasizes synthesis: Einstein's mechanics reveals 'more unity, more harmony, more beauty' in the universe. This is not mere rhetoric; it is a structural principle. Each chapter shows how previously separate phenomena—mechanics and optics, special relativity and gravitation—are brought under one law. The book itself mirrors this synthesis, moving from the particular (the Michelson-Morley experiment, implied in earlier chapters) to the general (the curvature of light by gravity). Pay attention to transitional phrases like 'we are now on the threshold' and 'it is thus that Einstein crowned his work.' They signal the cumulative nature of the argument. Nordmann's goal is not just to inform but to make the reader feel the elegance of the theory.

Nordmann's exposition rewards a reader who attends to his metaphors and analogies as carefully as to his scientific claims. The preface by Haldane offers a key: ordinary language can convey deep truths if used with precision. As you proceed, note how each chapter builds on the last, and how Nordmann returns to the image of gravitation as an island until it is finally annexed. This is a book that teaches not only relativity but a method of thinking about complex ideas without symbols.