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THE EXAMPLE LIBRARY

Engineering starts with a drawing.

Fourteen drawings from the existing historical archive, each paired with a contemporary question and an inspectable sketch model.

These are illustrative sizing exercises inspired by historical artifacts, rather than reconstructions of their dimensions or performance. Source credits and model limits accompany each example.

IMAGE → MODEL

See the Wright brothers drawing become an engineering overlay.

Inspect the historic source, register simplified geometry on top of it, and explore the assumptions behind a lift calculation. The current alignment is a manually adjusted illustration.

Try the Wright image-to-model overlay ↗
Leonardo da Vinci, Codex Atlanticus f. 1069 recto: pen sketches of water-raising machines, gear trains and pumpsc. 1482

Water-raising machines

How much shaft power lifts a chosen water flow?

View drawing and source model ↗Alexander Graham Bell's lab notebook, pp. 40–41, March 10, 1876: liquid transmitter sketch and the "Mr. Watson — Come here" entry1876

Liquid transmitter

How large is a static current change from a resistance perturbation?

View drawing and source model ↗Boulton & Watt double-acting engine (1784 design): beam, separate condenser and air pump, sun-and-planet gear, governorDrawing published 1878

Separate-condenser engine

What shaft power follows from an assumed mean effective pressure?

View drawing and source model ↗T. A. Edison, US 223,898 "Electric-Lamp", drawing sheet (carbon filament bulb)1880

Carbon-filament lamp

What current and power does an assumed hot filament draw?

View drawing and source model ↗N. Tesla, US 381,968 "Electro-Magnetic Motor", sheet 1 (rotating magnetic field figures)1888

Rotating-field motor

How do assumed slip and mechanical output set shaft speed and torque?

View drawing and source model ↗O. & W. Wright, US 821,393 "Flying-Machine", sheet 1 (wing structure with wing-warping)1906

Wing-warping aircraft

What airspeed gives enough idealized lift for an assumed mass?

View drawing and source model ↗R. H. Goddard, US 1,102,653 "Rocket Apparatus", sheet 1 (multi-stage rocket)1914

Multistage rocket

What ideal velocity budget results from two assumed stage mass ratios?

View drawing and source model ↗F. Whittle, US 2,168,726 "Propulsion of Aircraft and Gas Turbines", sheet 1 (turbojet cross-section). Used in place of GB 347,206 (see below)1939 (filed 1937)

Turbojet flow path

What momentum thrust follows from assumed inlet and exit conditions?

View drawing and source model ↗H. K. Markey (Hedy Lamarr) & G. Antheil, US 2,292,387 "Secret Communication System", sheet 11942

Synchronized frequency hopping

How much time remains after retuning and synchronization allowances?

View drawing and source model ↗R. B. Fuller, US 2,682,235 "Building Construction", sheet 1 (geodesic dome)1954

Geodesic structure

What axial stress follows for one idealized loaded strut?

View drawing and source model ↗G. de Mestral, US 2,717,437 "Velvet Type Fabric and Method of Producing Same" (hook-and-loop)1955

Hook-and-loop fastening

How large a bonded engagement area carries an assumed shear load?

View drawing and source model ↗J. S. Kilby, US 3,138,743 "Miniaturized Electronic Circuits", sheet 2 (Fig. 6a/6b: the flying-wire IC and its equivalent circuit). The drawing is sideways on the sheet, as published1964 (filed 1959)

Miniaturized circuit

How does assumed lumped parasitic capacitance limit a simple RC response?

View drawing and source model ↗D. C. Engelbart, US 3,541,541 "X-Y Position Indicator for a Display System", sheet 1 (the mouse)1970

X–Y position indicator

What surface displacement corresponds to one wheel-encoder count?

View drawing and source model ↗J. Dyson, US 4,593,429 "Vacuum Cleaning Appliance", sheet 1 (upright cleaner with cyclone and airflow arrows)1986 (filed 1984)

Cyclonic vacuum cleaner

How much fan shaft power supports an assumed flow and pressure drop?

View drawing and source model ↗