The original indexes to the wills, and probate and administration acts of the Prerogative Court of Canterbury, and of the other courts exercising probate jurisdiction.
The indexes were known as calendars, and were used, compiled, and annotated in the registries of the Prerogative Court of Canterbury, and its successors, the Court of Probate, and the Probate, Divorce and Admiralty Division of the High Court.
The indexes or calendars list the names of the testators and intestates of whose estates grants of probate and administration were made in that year.
The earliest stage in the compilation of the calendars appears to have been at the time of the grant of probate or administration when the name of the testator or intestate was written down in a bound volume of paper pages. The Court needed an immediate and accessible record of the issue of the grant of probate or administration, particularly to enable its officials to prevent the issue of more than one grant upon the same estate to separate applicants.
Each page of the volume was divided into two columns, and the names of testators were written in the left hand column and the names of intestates in the right hand column. At a later date the information in these calendars was transcribed into other calendars, and the transcripts were made available to searchers as a means of reference to wills, probate acts, and administration acts.