The results of a hemispheric experiment to investigate gravity waves with intrinsic periods between 0.5 and 3 hours are presented. Over 200 wave observations were made by using the vertical oscillations of drifting constant-volume balloons gathered with a pressure sensor, a temperature sensor, and an altimeter. Since these wave observations are 38% of the total sample, the results indicate that these waves are ubiquitous. All observations are made at nearly the same level in the atmosphere (140--170 mbar); at low latitudes the observations are in the tropical upper troposphere and at mid- and high latitudes they are in the lower stratosphere. The observed intrinsic frequency, the average amplitudes of the atmospheric pressure perturbation and vertical velocity, the vertical fluxes of wave energy and horizontal momentum, the total wave density, the vertical group velocity of the wave, and the wave action density are shown. The distributions of the average amplitudes show a few very large values for both regions. The distributions of vertical energy flux and vertical group velocity indicate that the dominate wave in the lower stratosphere of the mid- and high latitude is an evanescent or trapped wave, while in the upper tropical troposphere upward propagating, untrapped internal waves dominate. The distributions of wave action density are very similar for two regions, while the distributions of intrinsic frequency, total wave energy density, and vertical flux of horizontal momentum are different for the two regions. The balloon-borne observing system proved to be extremely good; however, the experimental system could be improved by making in situ measurements of the lapse rate and horizontal wind shear and by including a horizontal accelerometer. Such a completely instrumented system could prove to be very useful in determining how these waves influence the mean flow on a global scale.