In 2002, he presented the Royal Institution Christmas Lecture on Smart Stuff.
He also gave lectures, including the 1831 Royal Institution Christmas Lecture.
In 2005, Channel 5 acquired the right to the annual Royal Institution Christmas Lectures.
Among Inca's commissions were the filming of the Royal Institution Christmas Lectures.
He delivered the 1977 series of Royal Institution Christmas Lectures in London.
He presented the Royal Institution Christmas Lectures in 1988.
In 1899 he presented the Royal Institution Christmas Lectures.
Memorable among these were his Royal Institution Christmas Lectures to young people in 1966 and 1974.
In 1892, 1898 and 1900 he was invited to deliver the Royal Institution Christmas Lecture.
The latter includes the Royal Institution Christmas Lectures delivered in 1996.