Page:The Kinematics of Machinery.djvu/549

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CHAPTER XIII.
KINEMATIC SYNTHESIS.

"In magnis ct voluisse safest."—Propertius.

§ 138.
General Nature of Kinematic Synthesis.

Having now examined at some length and through a great variety of cases the problems of kinematic analysis, we come to the consideration of the reversed operation—kinematic synthesis. While the former showed us the nature of the constrained motions obtained by the use of given combinations of elements, links, or chains, the province of the latter (which has already been mentioned in § 3) is the determination of the pairs, chains, or mechanisms necessary to produce a given constrained motion.

This problem is the highest of those which here come before us, and perhaps the most important of the whole series, for it has for its immediate object the creation of new machines. For this reason, and also because its solution presupposes an acquaintance with kinematic analysis, it fitly forms the conclusion of our investigations. The reader who has followed these so far, however, cannot failed to have noticed that various synthetic propositions have presented themselves in the course of our work, both in the general view of machinery to which the history of its development led us, and also in our special examination of single