E. Cobham Brewer 18101897. Dictionary of Phrase and Fable. 1898.
Christs Hospital is so called because the boys there wear a long blue eoat girded at the loins with a leather belt. Some who attend the mathematical school are termed Kings boys, and those who constitute the highest class are Grecians.
Founded by Edward VI. in the year of his death. There are several other blue-coat schools in England besides Christs Hospital.