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.
A lighting ballast is necessary to operate discharge lights because they have negative resistance, meaning they are unable to regulate the amount of current that passes through them. A lighting ballast must be used to control current flow; otherwise the light could fail.