Please answer a question about the following article about Strasbourg:

A revolution in 1332 resulted in a broad-based city government with participation of the guilds, and Strasbourg declared itself a free republic. The deadly bubonic plague of 1348 was followed on 14 February 1349 by one of the first and worst pogroms in pre-modern history: over a thousand Jews were publicly burnt to death, with the remainder of the Jewish population being expelled from the city. Until the end of the 18th century, Jews were forbidden to remain in town after 10 pm. The time to leave the city was signalled by a municipal herald blowing the Grüselhorn (see below, Museums, Musée historique);. A special tax, the Pflastergeld (pavement money), was furthermore to be paid for any horse that a Jew would ride or bring into the city while allowed to.

What did the Jews need to pay to ride a horse into town?
special tax