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World's Oldest Periodic Table Chart Found At University of St Andrews In Scotland (phys.org)
An anonymous reader quotes a report from Phys.Org: A periodic table chart discovered at the University of St Andrews is thought to be the oldest in the world. The chart of elements, dating from 1885, was discovered in the University's School of Chemistry in 2014 by Dr. Alan Aitken during a clear out. The storage area was full of chemicals, equipment and laboratory paraphernalia that had accumulated since the opening of the chemistry department at its current location in 1968. Following months of clearing and sorting the various materials a stash of rolled up teaching charts was discovered. Within the collection was a large, extremely fragile periodic table that flaked upon handling. Suggestions that the discovery may be the earliest surviving example of a classroom periodic table in the world meant the document required urgent attention to be authenticated, repaired and restored.
Mendeleev made his famous disclosure on periodicity in 1869, the newly unearthed table was rather similar, but not identical to Mendeleev's second table of 1871. However, the St Andrews table was clearly an early specimen. The table is annotated in German, and an inscription at the bottom left -- "Verlag v. Lenoir & Forster, Wien" -- identifies a scientific printer who operated in Vienna between 1875 and 1888. Another inscription -- "Lith. von Ant. Hartinger & Sohn, Wien" -- identifies the chart's lithographer, who died in 1890. Working with the University's Special Collections team, the University sought advice from a series of international experts. Following further investigations, no earlier lecture chart of the table appears to exist. Professor Eric Scerri, an expert on the history of the periodic table based at the University of California, Los Angeles, dated the table to between 1879 and 1886 based on the represented elements. For example, both gallium and scandium, discovered in 1875 and 1879 respectively, are present, while germanium, discovered in 1886, is not.
Mendeleev made his famous disclosure on periodicity in 1869, the newly unearthed table was rather similar, but not identical to Mendeleev's second table of 1871. However, the St Andrews table was clearly an early specimen. The table is annotated in German, and an inscription at the bottom left -- "Verlag v. Lenoir & Forster, Wien" -- identifies a scientific printer who operated in Vienna between 1875 and 1888. Another inscription -- "Lith. von Ant. Hartinger & Sohn, Wien" -- identifies the chart's lithographer, who died in 1890. Working with the University's Special Collections team, the University sought advice from a series of international experts. Following further investigations, no earlier lecture chart of the table appears to exist. Professor Eric Scerri, an expert on the history of the periodic table based at the University of California, Los Angeles, dated the table to between 1879 and 1886 based on the represented elements. For example, both gallium and scandium, discovered in 1875 and 1879 respectively, are present, while germanium, discovered in 1886, is not.
A magnetic field, what exactly is it? Why is it at right angles to an electric field? How exactly is the interaction happening?
It's *NOT* from a flow of -ve charges in electrons. You have a magnetic field in light, but there's no electrons there. You have a flow of electrons in superconductivity but no magnetic field. Neither of those cases fit.
1. So it must be common to electrons and to light (and presumably all matter).
2. It must be connected to heat (because cooling causes superconductivity, aka loss of magnetic field)
3. It must be an interaction with electric force (because its at right angles to it)
4. It must created sometime by flow of electrons (because this is observed)
No name dropping dead physicists, no burying your head in an equation, simply explain what it is. I'm interested in hearing how its explained.