The earliest bills of mortality now in existence date back to the time of Henry VIII, when the clerks were required to furnish information with regard to the deaths caused by plague, as well as those resulting from other causes.  The returns of the victims of plague are occasionally very large.  In 1562, 20,372 persons died, of which number 17,404 died from the plague.  The burial grounds of the City became terribly overcrowded, and the parish clerks were ordered to report upon the space available in the City churchyards.  They also were appointed to see to “the shutting up of infected houses and putting papers on the doors.”

An early “Bill of Mortality” is preserved at the Hall.  It tells of “the Number of those who dyed in the Citie of London and Liberties of the same from the 28th of December 1581 to the 17th of December 1582, with the Christenings.  And also the number of all those who have died of the plague in every parish particularly.  Blessed are the Dead.”  There is also preserved a number of the weekly bills of mortality.  Referring to the year of the Great Plague, 1665, these documents show that at the beginning of the pestilence in April, during one week only fifty-seven persons died; whereas in September the death-roll had reached the enormous number of 6544.

The company seems to have been a useful agency for carrying out all kinds of duties connected with gathering the statistics of mortality, nor do they seem to have been overpaid for their trouble.  In the early years of the seventeenth century L 3. 6 s. 8 d. was all that they received.  In 1607 the sum was increased to L8, inasmuch as they were ordered to furnish a bill to the Queen and the Lord Chancellor as well as to the King.  Some clerks endeavoured to make illicit gains by supplying the public with “false and untrue bills,” or distributing some bills for each week before they had been sent to the Lord Mayor; and any brother who “by any cunning device gave away, dispersed, uttered, or declared, or by sinister device cast forth at any window, hole, or crevice of a wall any bills or notes” before the due returns had been sent to the Lord Mayor, was ordered to pay a fine of 10 s. and other divers penalties.

The methods of making out these returns are very curious, and did not conduce to infallible accuracy.  In each parish there were persons called searchers, ancient women who were informed by the sexton of a death, and whose duty it was to visit the deceased and state the cause of death.  They had no medical knowledge, and therefore their diagnosis could only have been very conjectural.  This they reported to the parish clerk.  The clerk made out his bill for the week, took it to the Hall of the company, and deposited it in a box on the staircase.  All the returns were then tabulated, arranged, and printed, and when copies had been sent to the authorities, others were placed in the hands of the clerks for sale.