The volume is a combined daybook and diary, with operating and statistical data entered on the left-hand leaves and notes on the occurrences of the day entered on the right-hand leaves. It comprises a relatively complete account of the operation of a Pine Barrens iron plantation. The diary appears to have been the work of a single primary writer from 1808 to 1811. Thereafter, three individuals seem to have been responsible for the entries, until the diary was discontinued in 1815. It was once thought that the principal writer was Caleb Earl, Jr., but this now appears less likely.

The daybook portion of the volume includes time sheets, lists of workmen, and records of consumption of raw materials and output of finished products. As such it is an important source on the technical performance of an early 19th century charcoal iron plantation. There are, however, no entries for wages paid or other dollar amounts, which were recorded in companion volumes that have not survived.

The diary portion of the volume is the work of a good observer of daily life and is an excellent source for the social history of an iron plantation. It mentions a total of 360 individual persons, including the workers, clerks, the visiting owners, and persons from the surrounding country doing business with the furnace. It describes work rhythms, celebrations, drunkenness, accidents, illnesses and deaths within the community, with occasional references to larger events in the world beyond the Pine Barrens. It also delineates the working relationships between Martha Furnace and nearby ironworks at Atsion, Batsto, Federal Furnace (Lakehurst), Hampton, Hanover and Weymouth.