Symbol (chemistry) the material was known in ancient times, while for others, the name is a more recent invention. For example, "He" is the symbol for helium (New Latin name, not known in ancient Roman times), "Pb" for lead ("plumbum" in Latin), and "Hg" for mercury ("hydrargyrum" in Greek). Some symbols come from other sources, like "W" for tungsten ("Wolfram" in German, not known in Roman times). Temporary symbols assigned to newly or not-yet synthesized elements use 3-letter symbols based on their atomic numbers. For example, "Uno" was the temporary symbol for hassium (element 108) which had the temporary name of "unniloctium".
Melting-point apparatus range to be recorded. A Thiele tube is a glass instrument that is filled with oil that is heated by using an open flame. The sample is placed in the opening in a capillary tube alongside a mercury thermometer and allowed to be heated by the oil as it circulates through the Thiele tube. By using different oils, different temperature ranges can be reached and used to determine melting points. The Thiele tube may also be used to determine boiling points, by using a liquid sample instead of a solid sample. Melting-point apparatus A melting-point apparatus is a scientific instrument