The majority of the contributing structures are commercial buildings built between about 1840 and 1939.

The design directly uses a majority of the already built civil structures and facilities related to generic plant needs.

The wide majority of the structures in the district were built between the fire of 1887 and about 1930.

The majority of the structures in the historic district have been maintained.

The majority of the structures within the district were built between 1880 and 1915.

The vast majority of the structures were designed to be temporary, and were torn down the following year, in 1906.

The majority of the structures associated with the Penniman facility was demolished somewhere between 1918 and 1925.

Significant flooding was reported, and the majority of the structures were completely destroyed.

The majority of the structures are made from black basalt, a volcanic rock found locally.

Following Barber's death in 1920, the majority of the structures on the farm were demolished.