An ornamental woodcut headpiece featuring a rectangular band of intricate scrolling foliate designs (arabesques) with a central oval medallion.

CHAPTER ONE.

ON CONSTRAINED MOTION IN GENERAL.

DEFINITION I.

A body is said to move in a constrained manner original: "non libere"; literally "not freely." In modern physics, this is referred to as "constrained motion," where a body is forced to stay on a specific path or surface when external obstacles prevent it from proceeding along that direction in which it ought to move, considering both its innate motion original: "motus insiti"; this refers to the motion or inertia a body already possesses and the nature of the impelling forces original: "potentiarum sollicitantium"; the external forces acting upon the body to change its state.

SCHOLION 1.

A "scholion" is an explanatory note or commentary used in historical scientific texts to provide further context for a definition or theorem.

2. Regarding the free motion of a point—which we explained in Part One—we assumed that the space in which the body moved was empty of all obstacles. Now, however, we shall consider space to be so arranged that the body is not permitted to proceed in every direction, due to firm barriers that do not allow passage.

The Latin catchword "Co-" refers to the first word of the next page, "Corpus" (Body).