AT the Nottingham meeting of the British Association a discussion on the upper air which was held on the morning of September 6 was preceded by a demonstration of the ascent of a sounding balloon, organized by Prof. D. Brunt. The demonstration attracted the attention of large numbers of members of the Association, as well as of the general public. The balloon carried a Dines meteorograph, recording pressure, temperature and humidity at all stages of the ascent. The instrument was attached to the balloon by a Baker release, which consists of a small aneroid box with a catch capable of being set so that it is released from the balloon at any desired height. In the demonstration the catch was set to liberate the instruments at a height of about 12 kilometres.