The first two digits represent the number of the grid area, the last five are assigned in sequence along leveling lines, usually streets, leaving gaps for insertion of additional or replacement bench marks. The limits of the sequence are shown by arrows. The ranges of the sequence are printed between the delimiting arrows. Occasionally a single bench mark will not be in a sequence and its number is shown on the index map at its approximate location. Bench mark information is retrievable by bench mark number or by description in conjunction with the index maps.
Descriptions are on the left side of each page with corresponding numbers at the extreme right.
Descriptions pertaining to bench marks of other agencies are not necessarily identical to those published by the other agency. Abbreviations are listed and defined at the end of this section. Notes pertaining to the status or physical condition of a bench mark may follow the descriptive text enclosed in asterisks. A bench mark that replaces a gone or abandoned one but is not in the identical location is regarded as a new bench mark and is assigned a new number. A bench mark number is never reassigned to a new bench mark or to a different bench mark.