Maskelyne, Nevil, astronomer-royal, born in London; determined the method of finding longitude at sea, and the density of the earth by experiments at Schiehallion, and commenced the “National Almanack,” and produced the first volume of “Astronomical Observations at Greenwich” (1732‒1811).
Definition taken from The Nuttall Encyclopædia, edited by the Reverend James Wood (1907)
Mask, Iron * Mason, Sir Josiah