The article notes that the block, which looks out upon Washington Park and the Old Stone House, "is now one of the most delightful blocks in Park Slope." We certainly agree with that assessment.
The buildings that were in such terrible shape 30 years ago are four story "double flats", i.e. two apartments per floor, perhaps built to house the families of workers employed in the industries ranged along the nearby Gowanus Canal. The buildings are apparently part of a row constructed in 1893 by local builder Charles Hagedorn (whose last name sometimes appears in variants including Hagedon, Hagadon, and Hagadorn).
"Building Intelligence; Houses; Brooklyn, N.Y., AABN vol. 40, no. 905 (April 29, 1893): p. xvii.
- Third St., n s, 175' w Fifth Ave., 12 four st'y brick dwells., tin roofs; cost, $7,500 each; owner, Chas. Hagadorn, 227 Thirteenth St.
The 1897 Lain's Brooklyn Directory lists Charles Hagedorn, lawyer, in residence at 227 13th Street, the same address as in the above AABN listing:
HAGEDORN Chas. lawyer h 227 13th
According to Brooklyn Eagle accounts, Charles Hagedorn was a substantial property owner along the 5th Avenue corridor, and was also president of the Fifth Avenue Property Holders' Rapid Transit Association, which was "anxious to see rapid transit along Fifth Avenue":
The campaign was successful and service along the new 5th Avenue line of the Brooklyn Elevated Railroad commenced in 1889.
The Brooklyn Daily Eagle in 1903 carried a photograph of one of the 3rd Street buildings when it was resold to a new investor. Note the awnings on the building to the left:
The entire row comprises twelve identical double flats, all now restored to near original condition.