We know of many others through looking through telephone and address books of the period. Others still have left behind them buildings, which are associated to varying extents with a specific profession. Some of these buildings are only available their residents. It is also worth mentioning places which were previously factories or production facilities, it became living quarters at a certain point in their history.
One of these hidden factories, surrounded by buildings on every side, is the Factory of Iron, Construction and Ornamental Goods ‘H. Zieliński,’ at Konopacki Street 17. The industrial plant functioned from 1860, and moved to New Praga after 1910. It primarily produced fire safes, but also fencing and apparatus for butcher’s shops and cold rooms. Another such example, or more specifically examples, are the Adolf Pypke Lace and Embroidery Factory and the Karol Jung and Ludwik Barwich Factory of Fittings and Sheet Metal Products at Inżynierska Street 5A and 5B. The Cyrillic inscription ‘Barwich ‘ has been preserved on the red brick elevation of the transverse outbuilding.
In Kamionek (Praga South) many plants, workshops and a bakery functioned in many periods at the address Targowa Street 14, in a tenement house built for Władysław Karszo- Siedlewski in the years 1899-190. Until recently, one could see the enamelled tablets there, giving information about who owned a business and where (the buildings span 4 lots.). One of the people who were entrepreneurs in the are in the 1930s and 1940s was Kazimierz Krzemiński, who had his mechanical plant at Targowa Street 14. Most likely, these types of businesses were focused on annexes on the third lot, or potentially on the fourth, where there are commercial buildings.