He soon found leisure and opportunity to fulfill a much-cherished wish, and spent the next few years on an extended tour of Italy, France and England. He used his "Wanderjahre" for the purposes of comparative study, and on his return in 1844 was appointed extraordinary professor of Roman law in the University of Berlin, and thus began a professorial connection which ended only with his death. The first fruits of his activity as a teacher were seen in his brilliant work, "Die formellen Verträge des heutigen römischen Obligationen-Rechtes" (Berlin, 1845). "Pari passu" with his academic labors he continued his judicial career, and became in due course successively assistant judge of the superior court and of the supreme tribunal. But to a mind constituted such as his, the want of elasticity in the procedure of the courts was galling. In the preface to his "Englische Verfassungsgeschichte", Gneist writes that he was brought up "in the laborious and rigid school of Prussian judges, at a time when the duty of formulating the matter in litigation was entailed upon the judge who personally conducted the pleadings, I became acquainted both with the advantages possessed by the Prussian bureau system as also with its weak points." Feeling the necessity for fundamental reforms in legal procedure, he published, in 1849, his "Trial by Jury", in which, after pointing out that the origin of that institution was common to both Germany and England, and showing in a masterly way the benefits which had accrued to the latter country through its more extended application, he pleaded for its freer admission in the tribunals of his own country.