The Palacio de los Patos is a posh residential building nuilt in 1929. It features 144 apartments spread across six floors. But while it may be posh today, the name eludes to the poverty of its residents. Gasp, shock, aw, que!? Poverty, here?
In 1929, when the stock market crashed, families that would have once lived in a single family home - or better said, a mansion or palacio - were now reduced to apartment life here. Pato is Lunfardo (Argentine slang) for impoverished. The term comes from the always dry feathers of ducks, to be poor is to be "dry." This is the Palacio de los Patos, the Palace of the Poor.
Fun fact: Borges mentions the buildings in El Aleph: "un laberinto es una casa labrada para confundir a los hombres, su arquitectura pródiga en simetrías, está subordinada a ese fin".