The law makes no special mandate. In 1789, Justice James Wilson was sworn in by the mayor of Philadelphia, Pennsylvania, where the court first sat. Thurgood Marshall, the nation's first African-American justice, took the Constitutional Oath in 1967 from Associate Justice Hugo Black, an Alabaman.
ballast - A device required by electric-discharge light sources such as fluorescent or HID lamps to regulate voltage and current supplied to the lamp during start and throughout operation.
For high-powered lights, however, a resistor would waste a large amount of electricity, so a more complex lighting ballast is required. An electromagnetic lighting ballast uses electromagnetic induction to provide the starting and operating voltages of a gas discharge light. Inside each is a coil of wire and an electromagnetic field that together transform voltage. Some also include an igniter for high-power applications.