The Glass Negative Collection comprises several glass plate negatives in which the developed photos appear in many of the City of Portland, Maine, Annual Report of the Commissioner of Public Works between 1892- 1920. They illustrate the work the Public Works Department was undertaking. In the reports, there are many photographs showing before the improvement were made and after the improvement were made on a given project. Portland Public Library has twenty glass plate negatives, eighteen measuring 8 x10 inches and two measuring 5 x 7 inches. Not all of the negatives resulted in publication in these annual reports.