published by Aero Digest in August 1948.liquid springs, general aviation

Bushfire behaviour is influenced by many factors including temperature, relative humidity (RH), forest type, fuel quantity and fuel dryness, topography and even slope. Wind has a dominant effect on the Rate of Spread (ROS), as well as fire size, shape and direction. Temperature and relative humidity have major impacts on fuel dryness and therefore upon the availability of fuel for combustion. The amount of fine fuel available can increase rapidly from nearly zero when fuel moisture content is more than 16% after rain or a heavy morning dew, to many tonnes per hectare as fuel dries out later in the day and the moisture content drops below 9%. This explosive escalation in the amount of available fuel can happen over a few hours on hot and windy days. This device is used for determining air temperature and relative humidity. It contains two thermometers, one of which is covered with a wick saturated with ambient temperature liquid water. These two thermometers are called dry bulb and wet bulb. Once the thermometers to reach equilibrium temperatures the two thermometers are quickly read. The figures are then used to convert the dry bulb temperature TDB and the wet bulb temperature TWB into humidity information. The wet bulb temperature is approximately equal to the adiabatic saturation temperature. Relative humidity meter in wooden box two stainless steel tubes contain wet and dry thermometers A small clock drives a fan motor in the base to circulate airforests commission victoria (fcv), weather, bushfire

Bushfire behaviour is influenced by many factors including temperature, relative humidity (RH), forest type, fuel quantity and fuel dryness, topography and even slope. Wind has a dominant effect on the Rate of Spread (ROS), as well as fire size, shape and direction. Temperature and relative humidity have major impacts on fuel dryness and therefore upon the availability of fuel for combustion. The amount of fine fuel available can increase rapidly from nearly zero when fuel moisture content is more than 16% after rain or a heavy morning dew, to many tonnes per hectare as fuel dries out later in the day and the moisture content drops below 9%. This explosive escalation in the amount of available fuel can happen over a few hours on hot and windy days. A sling psychrometer is a simple device for determining air temperature and relative humidity. It contains two thermometers, one of which is covered with a wick saturated with ambient temperature liquid water. These two thermometers are called dry bulb and wet bulb. When the sling psychrometer is spun rapidly in the air, the evaporation of the water from the wick causes the wet bulb thermometer to read lower than the dry bulb thermometer. After the psychrometer has been spun long enough for the thermometers to reach equilibrium temperatures, the unit is stopped, and the two thermometers are quickly read. A psychrometric scale on the side of the instrument is then used to convert the dry bulb temperature (TDB) and the wet bulb temperature (TWB) into humidity information. The wet bulb temperature is approximately equal to the adiabatic saturation temperature. The thermometers fold back into the plastic handle when not in use. Used to measure temperature and relative humiditySling PsychrometerBACHARACH INSTRUMENTS - Pittsburg PAbushfire, forests commission victoria (fcv)