His naturalization record gives his arrival as 12 December 1888. On 6 December 1888, I find a Heinr. Altman, aged 18, last of Krakau (Austria) arriving into New York aboard the Marsala out of Hamburg. This ship had left Hamburg on 16 November 1888. On the same ship is a Bernat Altman, aged 34, but residence is only given as Ungarn (Hungary). They are not listed together, so it may only be a coincidence that two passengers had the same last name.
Today, the city of Krakow is in Poland, near the border with both the Czech Republic and Slovakia. In 1888, this was all part of the Astro-Hungarian empire. It wouldnot have been unusual for him to have spoken several languages, including Hungarian.