INTRODUCTION This volume contains all of the data collected in the Los Angeles Basin by Scott Research Laboratories during the period August 22 to November 14@ 1958. The data has been reduced to meaningful units and presented in tabular form in four sections. Section 1 includes all data from the Huntington Park ground site. Section 2 includes El Monte ground data. Section 3 presents analytical data from airborne samples@ and Section 4 contains the complete log of all aircraft flight measurements. Chemical concentration data include those for carbon monoxide total hydrocarbons@ individual C1 to C10 hydrocarbons@ oxidant@ ozone@ nitric oxide@ nitrogen dioxide@ formaldehyde@ acrolein and total aliphatic aldehydes. Meteorological parameters recorded are temperature@ relative humidity@ wind speed and direction@ and ultraviolet radiation intensity. Total hydrocarbon concentrations greater than 8 ppm carbon are subject to error because of electronic damping of the instrument signal. All of the other categories of data have been examined and are believed to be valid@ although occasional erratic points must be anticipated in any such massive volume of data. A description of the methodology used to collect the data and a general explanation of the data including plots for selected days are given in Volxome I of this report. It is recommended that Sections 2 through 5 of Volume I be read before attempting any interpretation of the data in Volume II@