<div class="htmlview paragraph">Believing that a knowledge of definite, quantitative relations affecting the behavior of vehicle suspensions will lead to a better understanding of the problems of spring design, the author analyses the problem by considering it as a simple system (a single wheel supporting a weight by means of a frictionless spring), and by assuming that this system encounters certain elementary forms of irregularities.</div> <div class="htmlview paragraph">Analysis of this problem results in several expressions, the interpreting of which reveals the influence which the varying of specific factors has upon the action of the spring and its suspended load. These expressions take into account the effect of the ratio between sprung and unsprung weight, of speed, of size and kind of irregularity encountered by the wheel, tire inflation, flexibility of the spring, and wheel diameter. Other factors which are considered as a result of interpreting the curves presented are the effect of friction in the suspension, and of synchronism. Statements of the betterment which can be looked for in riding and steering qualities as a result of varying different factors are made. The effect of shock absorbers is discussed.</div>