expiation: making amends for, atonement.
Holy Sepulchre: the burial place of our Lord at Jerusalem, to rescue which from the Turks was the object of the Crusades.
[20. ST. BARTHOLOMEW'S HOSPITAL.]
Endowment: money given for the permanent support of an institution, such as a church, hospital, or school.
Hospitaller: one in charge of a hospital. The term is generally applied to the Knights of St. John, who built a hospital for sick Crusaders at Jerusalem.
shambles: a slaughter-house.
Whittington, originally an apprentice in London, became a wealthy mercer, thrice Lord Mayor, and knighted. He died in 1423, without children, and left his wealth for public objects, such as the one in the text.
Dissolution of the religious houses, carried out by Henry VIII. in 1536-1540 for the sake of the plunder they afforded.
Chloroform: a colourless liquid which when inhaled produces complete insensibility to pain.