An ornate engraved title page for a 1615 book on mechanical engineering and hydraulics. The scene is set within an architectural frame. At the very top, an armillary sphere a model of the celestial sphere with rings representing the great circles of the heavens rests on a plinth. Four putti (cherubs) are perched on the corners of the architecture: one at the top left blows bubbles; one at the top right holds a quadrant an instrument used to measure angles and altitudes in navigation and astronomy; two others are seated on lower ledges.

Beneath an architectural lintel bearing a Greek inscription, there is a central view of a harbor with sailing ships and a coastal city. Overlaid on this view is a large rectangular slab, shown in perspective, containing the book's title and author information.

Flanking the central scene are two niches containing statues:

To the left: Mercury holding a caduceus a winged staff entwined with two serpents, the symbol of the messenger god.
To the right: A female figure representing Nature.

At the bottom of the page, two classical figures are seated among various mechanical instruments:

On the left: Archimedes the famous Greek mathematician and engineer sits with a compass and a diagram.
On the right: Hero of Alexandria an ancient Greek engineer known for his work on steam and hydraulics points toward a large vertical pump or siphon.
The foreground is cluttered with mechanical parts, including gears, a large coiled spring or screw, a balance scale, pulleys, and a model of a water-driven organ or fountain.

Let no one ignorant of geometry enter

original: "ΜΗΔΕΙΣ ΑΓΕΩΜΕΤΡΗΤΟΣ ΕΙΣΙΤΩ", a famous motto famously associated with the entrance to Plato's Academy.

THE REASONS

OF MOTIVE FORCES

With various Machines

Both useful and pleasant

To which are added

several designs for grottoes

and fountains

By

SALOMON DE CAUS

Engineer and architect to his

Electoral Palatine Highness.

This refers to Frederick V, the Elector Palatine, whom De Caus served in Heidelberg.

In Frankfurt, at the shop of John Norton.

1615

Mercury

Nature

Archimedes

Hero of Alexandria original: "Herone Alexandrine"