Showing the effect of a wind storm that destroyed the house circa May 1962.. The Abraham family owned land near the Aqueduct and east of Nicholas Lane at Kangaroo Ground (based on photos, at or near 40 Nicholas Lane).Record of various Shire of Eltham infrastructure works undertaken during the period of 1952-1962 involving bridge and road reconstruction projects, sometimes with Eltham Shire Council Project Reference numbers quoted. It was during this period that a number of significant improvements were made to roads and new bridges constructed within the shire that remain in place as of present day (2022). In many situations, the photos provide a tangible visible record of infrastructure that existed throughout the early days of the Shire. The album was put together by or under the direction of the Shire Engineer, J.A. McDonald.1962-05, abraham house, kangaroo ground, nicholas lane, property damage, storm damage

Showing the effect of a wind storm that destroyed the house circa May 1962.. The Abraham family owned land near the Aqueduct and east of Nicholas Lane at Kangaroo Ground (based on photos, at or near 40 Nicholas Lane).Record of various Shire of Eltham infrastructure works undertaken during the period of 1952-1962 involving bridge and road reconstruction projects, sometimes with Eltham Shire Council Project Reference numbers quoted. It was during this period that a number of significant improvements were made to roads and new bridges constructed within the shire that remain in place as of present day (2022). In many situations, the photos provide a tangible visible record of infrastructure that existed throughout the early days of the Shire. The album was put together by or under the direction of the Shire Engineer, J.A. McDonald.1962-05, abraham house, kangaroo ground, nicholas lane, property damage, storm damage

Showing the effect of a wind storm that destroyed the house circa May 1962.. The Abraham family owned land near the Aqueduct and east of Nicholas Lane at Kangaroo Ground (based on photos, at or near 40 Nicholas Lane).Record of various Shire of Eltham infrastructure works undertaken during the period of 1952-1962 involving bridge and road reconstruction projects, sometimes with Eltham Shire Council Project Reference numbers quoted. It was during this period that a number of significant improvements were made to roads and new bridges constructed within the shire that remain in place as of present day (2022). In many situations, the photos provide a tangible visible record of infrastructure that existed throughout the early days of the Shire. The album was put together by or under the direction of the Shire Engineer, J.A. McDonald.1962-05, abraham house, kangaroo ground, nicholas lane, property damage, storm damage

Showing the effect of a wind storm that destroyed the house circa May 1962.. The Abraham family owned land near the Aqueduct and east of Nicholas Lane at Kangaroo Ground (based on photos, at or near 40 Nicholas Lane).Record of various Shire of Eltham infrastructure works undertaken during the period of 1952-1962 involving bridge and road reconstruction projects, sometimes with Eltham Shire Council Project Reference numbers quoted. It was during this period that a number of significant improvements were made to roads and new bridges constructed within the shire that remain in place as of present day (2022). In many situations, the photos provide a tangible visible record of infrastructure that existed throughout the early days of the Shire. The album was put together by or under the direction of the Shire Engineer, J.A. McDonald.1962-05, abraham house, kangaroo ground, nicholas lane, property damage, storm damage

Showing the effect of a wind storm that destroyed the house circa May 1962.. The Abraham family owned land near the Aqueduct and east of Nicholas Lane at Kangaroo Ground (based on photos, at or near 40 Nicholas Lane).Record of various Shire of Eltham infrastructure works undertaken during the period of 1952-1962 involving bridge and road reconstruction projects, sometimes with Eltham Shire Council Project Reference numbers quoted. It was during this period that a number of significant improvements were made to roads and new bridges constructed within the shire that remain in place as of present day (2022). In many situations, the photos provide a tangible visible record of infrastructure that existed throughout the early days of the Shire. The album was put together by or under the direction of the Shire Engineer, J.A. McDonald.1962-05, abraham house, kangaroo ground, nicholas lane, property damage, storm damage

Showing the effect of a wind storm that destroyed the house circa May 1962.. The Abraham family owned land near the Aqueduct and east of Nicholas Lane at Kangaroo Ground (based on photos, at or near 40 Nicholas Lane).Record of various Shire of Eltham infrastructure works undertaken during the period of 1952-1962 involving bridge and road reconstruction projects, sometimes with Eltham Shire Council Project Reference numbers quoted. It was during this period that a number of significant improvements were made to roads and new bridges constructed within the shire that remain in place as of present day (2022). In many situations, the photos provide a tangible visible record of infrastructure that existed throughout the early days of the Shire. The album was put together by or under the direction of the Shire Engineer, J.A. McDonald.1962-05, abraham house, kangaroo ground, nicholas lane, property damage, storm damage

Showing the effect of a wind storm that destroyed the house circa May 1962.. The Abraham family owned land near the Aqueduct and east of Nicholas Lane at Kangaroo Ground (based on photos, at or near 40 Nicholas Lane).Record of various Shire of Eltham infrastructure works undertaken during the period of 1952-1962 involving bridge and road reconstruction projects, sometimes with Eltham Shire Council Project Reference numbers quoted. It was during this period that a number of significant improvements were made to roads and new bridges constructed within the shire that remain in place as of present day (2022). In many situations, the photos provide a tangible visible record of infrastructure that existed throughout the early days of the Shire. The album was put together by or under the direction of the Shire Engineer, J.A. McDonald.1962-05, abraham house, kangaroo ground, nicholas lane, property damage, storm damage, building surveyor, george e. newton

Showing the effect of a wind storm that destroyed the house circa May 1962.. The Abraham family owned land near the Aqueduct and east of Nicholas Lane at Kangaroo Ground (based on photos, at or near 40 Nicholas Lane).Record of various Shire of Eltham infrastructure works undertaken during the period of 1952-1962 involving bridge and road reconstruction projects, sometimes with Eltham Shire Council Project Reference numbers quoted. It was during this period that a number of significant improvements were made to roads and new bridges constructed within the shire that remain in place as of present day (2022). In many situations, the photos provide a tangible visible record of infrastructure that existed throughout the early days of the Shire. The album was put together by or under the direction of the Shire Engineer, J.A. McDonald.1962-05, abraham house, kangaroo ground, nicholas lane, property damage, storm damage

This representative example demonstrates a mariner’s astrolabe. Historical examples are rare. There are less than one hundred known to exist and most of these have been recovered from shipwrecks, many from Spanish and Portuguese vessels. An astrolabe is a measuring device once used to navigate the seas by observing the sun and stars to measure their altitude. The measurement of altitude could then be used to calculate the ship’s latitude but at that time in history there was no means of measuring longitude. The body of the navigational astrolabe was cast brass and much heavier, and less complicated than the variety used on land. The heavier weight and cut-away shape reduced the effect of the wind and waves when trying to use it at sea. A mariner’s astrolabe or ‘star finder’ is a simplified version than that used by Arabic astronomers to find the altitude of the sun and stars above the horizon, and time of the sunrise and sunset. It is a forerunner to the quadrant, octant and sextant and was popular for about 200 years over the 1500s and 1600s to find the latitude of a ship at sea. The user held the astrolabe at eye level and, usually with assistance, aligned the stars through the two small sights (pinnules), then read the altitude indicated by the pointer on the arm. It could also be used to sight the sun by holding it lower down, aiming it at the sun, and adjusting it until the sun shone through both pinnules. This astrolabe is an example used to demonstrate the mariner’s astrolabe, which was navigational tool of the 1500s and 1600s, in the time before longitude was able to be determined. It is a forerunner to modern navigation technology. Mariner’s astrolabe – a representative example. A gold painted, disc shaped object with cut outs and revolving arm in centre. The arm has two sights attached at right angles. The top has a ring attached. Measurements are marked in degrees in a circular scale around outer edge.flagstaff hill, warrnambool, maritime village, maritime museum, flagstaff hill maritime museum & village, shipwreck coast, great ocean road, navigation instrument, navigation tool, navigation, astrolabe, mariner’s astrolabe, measure latitude, measure altitude, arabic navigation, measuring device, star finder, astronomy, marine tool, marine instrument

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. A thermo-hygrograph measures and records both temperature and humidity. It produces a continuous record by drawing ink traces on a paper chart held in revolving cylinder. Humidity is measured by shortening or lengthening of specially treated horse hair. Temperature is measured by means of a bi-metallic strip. This particular instrument is a seven day recorder. The instrument is driven by clockwork. Thermo-hygrographNegretti & Zambra

Bushfire behaviour is influenced by many things including temperature, relative humidity, forest type, fuel quantity and fuel dryness, topography and even slope. Wind has a dominant effect on the Rate of Spread (ROS), and also bushfire size, shape and direction. Fuel arrangement is as important as fuel quantity (tonnes/ha). Fibrous and ribbon bark, together with elevated and near-surface scrub fuels act as ladders which lead flames into the tree canopy. But the availability of fuel to burn depends largely on its moisture content. When it exceeds 20-25% not much will burn, whereas 12-15% is generally ideal for fuel reduction burning, but if the moisture content drops as low as 7-10% virtually everything will ignite, and fire behaviour becomes extreme. During the afternoon of the Ash Wednesday bushfires on 16 February 1983 fuel moisture contents were recorded at Stawell as low as 2.7%. Fine fuels like leaves and bark can rapidly absorb moisture after a shower of rain, or from the air when the Relative Humidity (RH) is high, and the temperature is low. Conversely, they can also dry out very quickly. So even though the overall fuel quantity in the forest doesn’t change, the fine fuel availability can increase rapidly from zero after rain to many tonnes per hectare as the fuel dries out. This can happen over a few hours on hot and windy days. Heavy fuels like logs on the ground take longer to dry out. Since the 1930s foresters, firefighters and researchers have been working to develop quick and reliable techniques for measuring fuel moisture content. One of the most accurate methods is slowly drying a sample of fuel in a conventional oven for 24-48 hours to remove all the moisture and measuring the weight difference, but this takes time and is not practical in the field when rapid measurements are needed. But oven drying is often used as a benchmark to compare other methods. Microwave ovens are faster but can cause uneven drying and even char the fuel. They are also not very practical for use in the field. Some mathematical models rely on weather records such as rainfall, wind speed, evaporation, cloud cover, shading, relative humidity, slope, aspect and season of the year to predict soil and fuel moisture. The Keetch-Byram Drought Index of soil dryness is the most common. But complex fuels with leaves, twigs, grass etc make the predictive models often inadequate for fine fuels. The most common technique in Victorian forests until recently was the trusty Speedy Moisture Meter. Originally developed in England during the 1920s for measuring moisture in wheat and other grains it was adapted for Australian forest fuels in the 1950s (I think). Fuel was first ground using a Spong mincer, often attached to the bullbar of a vehicle, and a small sample placed into the Speedy together with a measure of calcium carbide and then sealed. A chemical reaction created gas pressure which was read on the external dial. There were important techniques with cleaning, mincing and using the chemicals with the Speedy to give reliable readings, but it was quick, inexpensive, robust, portable and practical in the field. It was used routinely before igniting a fuel reduction burn or measuring fuel moisture differentials on slash burns. But in about 1996, Karen Chatto and Kevin Tolhurst from the Department’s Creswick Research Station developed the Wiltronics Fuel Moisture meter which measured electrical resistance. Wiltronics is an Australian owned company operating from Ballarat. The final result was a kit that was portable, accurate and could reliably measure fuel moisture contents between 3% and 200%. Although expensive, it is now widely used by fire agencies around the world which has virtually relegated the Speedy to the back cupboard.Prototype Fuel moisture meterT-H Fine Fuel Meterforests commission victoria (fcv), bushfire, forest measurement

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)

Bushfire behaviour is influenced by many factors including temperature, relative humidity (RH), forest type, fuel quantity and fuel dryness, topography and even slope. But wind has a dominant effect on the Rate of Spread (ROS), as well as fire size, shape and direction. Wind speed can be measured using a variety of anemometers. This simple hand-held Venitimer was made by Elvometer in Sweden, probably in the 1960s, and was designed principally for mariners. Some models have a compass in the handle to measure wind direction. The small inlet hole on the side is faced towards the wind and air pressure lifts a small plastic disk inside. The upper tube is tapered so that as wind speed increases more air escapes and stronger winds are needed to raise the disk. Wind speed in MPH is read from the side of the clear plastic tube. The waterproof container has instructions on use and conversion scales. Simple and robust device.Hand-held anemometer Instructions on use on containerbushfire, forests commission victoria (fcv)

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. A thermo-hygrograph measures and records both temperature and humidity. It produces a continuous record by drawing ink traces on a paper chart held in revolving cylinder. Humidity is measured by shortening or lengthening of a bundle of specially treated human hair. Temperature is measured by means of a laminated bi-metal strip of temperature-sensitive metals which bend differentially with temperature change. The recording drum is driven by clockwork which may be geared for rotation intervals of daily, weekly or monthly periods. This particular instrument is a seven-day recorder. Serial number 10186 which probably dates from about 1960. The chart indicates it was last used in March 1979.Used for bushfire research.Clockwork Thermo-hygrographCasella London 10186 Made in England Research Branch. Forests Commission Orbostbushfire, forests commission victoria (fcv), forest measurement