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Due to the condition of the original material, there are unavoidable flaws in this reproduction. We have made every effort possible to provide you with the best copy available. If you are dissatisfied with this product and find it unusable, please contact Document Services as soon as possible. Author's Abstract: The basic problem is to determine whether or not a satisfactory method can be developed for the continuous measurement of blood pressure by indirect techniques. Upon the establishment of some overall criteria, and with a survey into the field, various possible approaches to the problem are considered. Each of the possible approaches is preliminarily analyzed, and the most realistic possibility is analyzed in detail. The technique which is studied in detail is based on a pressure variable parameter of the cardiovascular system. This parameter is arterial volume. It is shown that the arterial volume is quasi-linearly related to intra-arterial pressure for a theoretical model, and that experimental data substantiates this analysis. The logic behind the pressure variable parameter system is simply; since volume can be measured externally with greater ease that pressure, then with a relatively simple system blood pressure can be monitored. A theoretical analysis and experimental documentation is made for each assumption in the proposed theory. Based on the proposed theory, a developmental transducer system is proposed and built. With various analyses, the transducer is modified and ultimately, a linearized transducer is presented. With a linearized capacitance transducer, the system is subjected to clinical conditions, and various effects are measured and analyzed. The results of a preliminary program of analysis indicate that under controlled conditions, the proposed system has some significant potentialities. Over short periods of time, the system is able to record human blood pressure continuously to an accuracy of a few percent. It should be noted that under certain clinical conditions, the proposed theory appears to be completely invalid. These conditions limit the effectiveness of the proposed device. With further development, the author feels that some of-the present limitations can be overcome. A program for further development work is suggested, along with a new transducer the design of which is based on the information gained by the present analysis.