My contribution to this most interesting discussion is this link to the 1894 Buffalo City Atlas, which shows just about all the building lots and the buildings on them that existed when the data was collected. (http://www.erie.gov/atlases/buff_94/city_atlas.html).
The lot widths and lengths are listed along with the street numbers. The buildings are also shown, along with the number of stories as well as composition (ie, red for brick and yellow for wooden). Businesses, churches, schools, etc are identified.
This atlas is from the time when Buffalo was growing but hadn't yet been "swamped" with newcomers (primarily European immigrants). What you see is that large areas of the city outside of downtown were either still farmland or "suburban" type developments. Also the tradition of deep narrow lots seems well entrenched.
Some time in the 1890s I believe, NYS prohibited cities from annexing of surrounding areas, which meant that Buffalo couldn't expand outward. I think that contributed to the development of very dense urban neighborhoods as the city's population grew. The lots were replatted to 30' wide and whole neighborhoods of two-family homes were built (up and down apartments). Also, many neighborhoods added additional houses on the same lot. You see some of that on the atlas, but it became quite common in many working class neighborhoods later on.


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some are big and some small.