Impulse, in Mechanics, the single or momentary action or force by which 2 body is impelled by another body striking it, and is distinguished from continued force, such as pulling, pushing, or pressure. Mr. Adams, in his Lectures on Natural and Experimental Philosophy, justly observes, " We are forced, by the evidence of every phenomenon in nature, by every experiment in philosophy, to conclude that impulse is the only material cause of motion. All the properties of matter are such as fit them to act, and to be acted upon, in a mechanical way. They are all such as can be adapted to the known principles of mechanism among artists. We are therefore bound by every rule of sound reasoning, to consider it as the cause of all the motion, and continuance of motion, in the material universe. It is the one certain .and only universally known cause; for neither the properties of matter, nor experiment, nor observation, afford any other."