"Brochstat" isn't in the Oxford dictionary but sounds like the surname of a German or German Jew living in Russia. "Brodsky" would come from someone whose forefather had the same given name as someone else in his village, but he lived near the ford of a river or brook. "Brodsky" means "from near the ford," or just "ford" as an adjective rather than a noun.

"There are few towns in Western Ukraine with so dramatic and challenging Jewish history as it is in case of Brody. For a long time Brody had been one of the greatest centers of commerce in the whole Austro-Hungarian empre. It was rightly referred to as Triest on the continent. The town has been known yet since the 12th century and soon after was almost entirely inhabited by the Jews. Because of the last fact it came known to be as Galician Jerusalem." "The city name Brody derives from Ukrainian word “brid” which means “ford” (German Furt) changing in plural into “brody” i.e. “fords”. " "Hundreds of Jews all over the world trace their roots to Brody and as a result of it, many adopted the last name Brodsky, Brodski, Brodskiy, Brodowski, Brodovsky, Brodisch (meaning “from Brody”) or simply Brody." Source and further information: "Galician Jerusalem Brody as Jewish Intellectual and Cultural Hub of Eastern Galicia" www.personal.ceu.hu/students/97/Roman_Zakharii/brody.doc Further information about Brody (city in Ukraine): http://en.wikipedia.org/wiki/Brody Brody Ghetto: http://www.deathcamps.org/occupation/brody%20ghetto.html Unfortunately, I did not found any information about "Brochstat". It could be a Germanic / Yiddish form of the same.