Cor. 1. In non-reſiſting ſpaces or mediums, if the areas are not proportional to the times, the forces are not directed to the point in which the radii meet; but deviate therefrom in conſequantia, or towards the parts to which the motion is directed. if the deſcription of the areas is accelerated; but in antecedentia, if retarded.
Cor. 2. And even in reſiſting mediums, if the deſcription of the areas is accelerated, the directions of the forces deviate from the point in which the radii meet, towards the parts to which the motion tends.
Scholium
A body may be urged by a centripetal force compounded or ſeveral forces. In which caſe the meaning of the propoſition is, that the force which reſults out of all, tends to the point S. But if any force, acts perpetually in the direction of lines perpendicular to the deſcrib'd ſurface; this force will make the body to deviate from the plane of its motion: but will neither augment nor diminiſh the quantity of the deſcribed ſurface, and is therefore to be neglected in the compoſition of forces.
