Low-temperature technology timeline

The following is a timeline of low-temperature technology and cryogenic technology (refrigeration down to close to absolute zero, i.e. –273.15 °C, –459.67 °F or 0 K). It also lists important milestones in thermometry, thermodynamics, statistical physics and calorimetry, that were crucial in development of low temperature systems. – Zimri-Lim, ruler of Mari in Syria commanded the construction of one of the first ice houses near the Euphrates. – The yakhchal (meaning "ice pit" in Persian) is an ancient Persian type of refrigerator. The structure was formed from a mortar resistant to heat transmission, in the shape of a dome. Snow and ice was stored beneath the ground, effectively allowing access to ice even in hot months and allowing for prolonged food preservation. Often a badgir was coupled with the yakhchal in order to slow the heat loss. Modern refrigerators are still called yakhchal in Persian. Hero of Alexandria knew of the principle that certain substances, notably air, expand and contract and described a demonstration in which a closed tube partially filled with air had its end in a container of water. The expansion and contraction of the air caused the position of the water/air interface to move along the tube. This was the first established principle of gas behaviour vs temperature, and principle of first thermometers later on. The idea could predate him even more (Empedocles of Agrigentum in his 460 B.C. book On Nature). 1396 AD - Ice storage warehouses called "Dong-bing-go-tango" (meaning "east ice storage warehouse" in Korean) and Seo-bing-go ("west ice storage warehouse") were built in Han-Yang (currently Seoul, Korea). The buildings housed ice that was collected from the frozen Han River in January (by lunar calendar). The warehouse was well-insulated, providing the royal families with ice into the summer months. These warehouses were closed in 1898 AD but the buildings are still intact in Seoul. 1593 – Galileo Galilei builds a first modern thermoscope.