An aneroid barometer is an instrument used for measuring air pressure as a method that does not involve liquid. Invented in 1844 by French scientist Lucien Vidi, the aneroid barometer uses a small, flexible metal box called an aneroid cell (capsule), which is made from an alloy of beryllium and copper. The evacuated capsule (or usually several capsules, stacked to add up their movements) is prevented from collapsing by a strong spring. Small changes in external air pressure cause the cell to expand or contract. This expansion and contraction drives mechanical levers such that the tiny movements of the capsule are amplified and displayed on the face of the aneroid barometer. Many models include a manually set needle which is used to mark the current measurement so a change can be seen. This type of barometer is common in homes and in recreational boats. It is also used in meteorology, mostly in barographs and as a pressure instrument in radiosondes.5 inch Aneroid barometer on wooden basebarometer, aneroid

An aneroid barometer is an instrument used for measuring pressure without the use of a liquid. Invented in 1844 by French scientist Lucien Vidi, the aneroid barometer uses a small, flexible metal box called an aneroid cell (capsule), which is made from an alloy of beryllium and copper and responds to changes in air pressure.An example of a widely used type of barometer.A brass aneroid barometer with a white face.Manufactured by C. Wermer and Co, Melbournebarometer, aneroid barometer, c. wermer

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)