Thermal analysis cuts a broad swathe through contemporary science. Within this domain, advances in instrumentation permit the application of quantitative calorimetry to the full spectrum of modern materials. This can be illustrated perhaps no better than by the set of contributions which make up this Volume 4 of Analytical Calorimetry. The research supported in this fourth volume of Analytical Calorimetry covers a wide variety of topics. The range indicates the sophistication which thermal analysis is reaching and additional­ ly the ever-widening applications that are being developed. The contributions to the Volume represent, in part, papers presented before the Division of Analytical Chemistry at the Fourth Symposium on Analytical Chemistry held at the 172nd National Meeting of the American Chemical Society, August 29 - September 3, 1976. Several additional key contributions are included by prominent workers in the field. Julian F. Johnson Roger S. Porter v Quantitative Scanning Calorimetry with Computerized Data Acquisition and Reduction . . . . . . . 1 Aris Doelman, Annie R. Gregges, and Edward M. Barrall, II Thermodynamic Properties of a Series of P-N-Alkyl-P'-Cyanobiphenyls 19 E. M. Barrall II, R. J. Cox, A. Doelman, N. Clecak, J. A. Logan, and A. R. Gregges Thermodynamic Properties of a Series of 37 P-N-Alkoxy-P'-Cyanobiphenyls R. J. Cox, E. M. Barrall II, A. Doelman, N. J. Clecak, J. A. Logan, R. D. Diller, and A. R. Gregges A New Equation for Predicting Polyethylene Lifetimes from Thermal Data 51 Cary F.