ABSTRACT
This chapter explains the processes by which mass and heat energy are moved about in the air. Water comprises an important part of the mass to be moved and temperature defines the condition or state of the heat energy involved. Different body functions control the internal transfers of water and heat. These respond in turn to external mechanisms stimulated by behaviour and contact with the atmosphere. Oxygen is the most abundant element of the Earth-atmosphere system. Even the remaining 1% of the air is dominated by recombinations of oxygen. The reader who is probably at rest in a room with adequate amounts of moisture and warmth, provides an energy gradient for transfers of both mass and heat from the person to the surrounding air. The melting and boiling points of water of 0°C and 100°C respectively are many times higher than for similar substances with low molecular weights.
