Kingdom of Hungary Máté Csák III. The kingdom of Hungary reached an age of prosperity and stability under Charles I. The gold mines of the Kingdom were extensively worked and soon Hungary reached a prominent standing in European gold production. The forint was introduced as a currency, replacing the "denars", and soon after Charles's reforms were implemented, the economy of the Kingdom started to prosper again, having fallen into a parlous state following the Mongol invasion. Charles exalted the cult to Saint Ladislaus I, using him as a symbol of bravery, justice and purity. He also venerated his uncle, Saint Louis of Toulouse.
Ring main unit type of switchgear is used for medium-voltage power distribution, from 7200 volts to about 36000 volts. The ring main unit was introduced in the United Kingdom and is now widely used in other countries. In North American distribution practice, often the equivalent of a ring main unit is built into a pad-mounted transformer which integrates switches and transformer into a single cabinet. Ring main units can be characterized by their type of insulation, air, oil or gas. The switch used to isolate the transformer can be a fusible switch, or may be a circuit breaker using vacuum or gas-insulated interrupters.