Isaac Nordheimer (1809-1842) was a 19th century Hebraist, notable today chiefly for having adopted America as his place of domicile. He was also a former student at the Pressburg Yeshiva. As far as I know there is only one account of his life, and this was written upon his death by a friend, Edward Robinson (yes, of Robinson's Arch fame), in the latter's journal the Bibliotheca Sacra and Theological Review. This account was published upon Nordheimer's untimely death due to tuberculosis and, to give an idea of how he was seen as a scholar in his own time, the notice about Nordheimer follows one about another recently departed Hebraist, no less than Gesenius. Of course this does not mean that Robinson considered Nordheimer the equal of Wilhelm Gesenius, but he was seen as worthy of mention in the same breath ("Biographical Notices of Gesenius and Nordheimer").
In any case, in the biography (link) some aspects of Nordheimer's years at the Pressburg Yeshiva are recorded, told to Robinson by the late scholar. For example, Nordheimer had told him that he made the [nearly 400 mile] journey from his hometown in Bavaria to Pressburg at age 13, partly on foot. Robinson says that the Chatam Sofer took a personal interest in the boy.
There is the following description of what some of the bochurim did to make sure they did not oversleep after staying up late to learn in the Beit Midrash: