void readProperties() throws Exception {
    logger.log("Reading PROPARC properties records...");
    while (readLine() != null
        && (line.length() < 10 || !line.substring(0, 10).equals("ENDPROPARC"))) {
      if (line.length() >= 4 && line.substring(0, 4).equals("PROP"))
        readProperty();
      if (line.length() >= 6 && line.substring(0, 6).equals("DIPOLE"))
        readDipole();
      if (line.length() >= 7 && line.substring(0, 7).equals("VIBFREQ"))
        readVibFreqs();
    }
  }