The city copies of subdivision plats, filed with the superior court since 1851. The series also contains survey and easement plats. The latter encompass streets, railroads, and utilities. Some condominium plats were recorded within the plat books rather than the separate system for such documents. In general the documents are arranged chronologically by filing date, and referenced with book and page numbers or book and plat numbers. The plats for 1851-1922 were recorded in seven volumes. Those for 1922-1946 were recorded within (Land Records) in series C205 either on individual pages or pockets attached to the book covers, and are described within (Plats from Land Records) in series C2868. In 1946 the court switched to a sequential numbering system for plats, but retained the book concept by assigning each clerk's initials to groups of plats. The size of each group varies between 80 and 800 items. In 1978 the court began a program to maintain its plats only on aperture cards as found in (Plat Book, Aperture Cards) in series C2828 and C2829. Originals are sent to the State Archives. The plats in this series C2827 will be used to supplement (Subdivision Plats, BC) in series S1237 as needed to fill in gaps or provide more complete or clearer copies. The records for 1851-1922 will be scanned only within C2827. Access available in electronic form derived from (Plats, Index) in series C2835, supplemented by the records themselves.