Measurements of large apparent D. C. electric fields (~V/m) in the middle atmosphere made by two sounding rockets are carefully analyzed and shown to be spurious. This may shed some doubt on recent measurements of large D. C. electric fields by other experimenters. Evidence is presented, for one rocket,indicating that the measured electric fields are aligned with the velocity vector of the rocket. This suggests the possibility that the measured electric fields are due to a negatively charged wake. A comparison of measurements made by different electric field booms is also presented. We see that in one experiment insulating coatings on the booms may have affected our results. It is the authors' opinion that insulating coatings should not be used at mesospheric altitudes because of possible detrimental effects such as frictional charging.