Data were obtained from four balloon‐launched Deacon rockets during the summers of 1953 and 1954, without the aid of groundbased trajectory measurements. The atmospheric density profile in the 25‐ to 45‐km region was found within the experimental error to be the same as the Rocket Panel, White Sands values. The measured atmospheric pressure and the computed temperature for the flights at 62° and 74° north were found to be up to 30 percent higher in the 30‐ to 45‐km region, but approximately equal to the White Sands values at 70 km. At 74° north, a high lapse‐rate is indicated within the regi