Your doctor may need to change the doses of your medications or monitor you carefully for side effects. ... Metformin side effects can also affect other parts of the body. It can leave a metallic taste in the mouth, cause heartburn or headache, flushing of the skin, nail changes or muscle pain. More serious metformin side effects include chest pain or rash. ...
Early String Theory. The first attempt to construct a physical model of an atom was made by William Thomson (later elevated to Lord Kelvin) in 1867. The most striking property of the atom was its permanence.
The next great step forward in the understanding of atoms was accomplished by John Thomson. Using a cathode ray scope, Thomson determined that all matter, whatever its source, contains particles of the same kind that are much less massive than the atoms of which they form a part.