In 1848, Wisconsin had been added to the Union as a free state, and there were now in the Union sixteen free states and fifteen slave states, giving to the free states the preponderance in the Senate, as they had long had in the lower House. Neither Utah nor New Mexico was fitted at all for slave labor, and there was no territory out of which it was likely that another slave state could be formed, except by the sub-division of Texas, while there was a prospect for the formation of several more free states, at no distant day, out of the territory west of the Mississippi and north of 36° 30´ and on the Pacific coast, the territories of Minnesota and Oregon having already been organized. By what was called the Compromise of 1850, the South had gained nothing whatever, except the abstract principle inserted in the Utah and New Mexico bills, of non-interference by Congress with the question of slavery and the submission of the decision of the question to the people of the territories when they came to frame their state governments, while the North had gained the rich and growing state of California. The bill for the restoration of fugitive slaves was in accordance with an express stipulation in the Constitution, without which it would never have been adopted. Yet the execution of this law was resisted from the very beginning and very soon most of the free states passed laws, called "personal liberty bills" which virtually nullified the act of Congress. Several collisions ensued between the United States officers in their efforts to execute the law and mobs in the free states who resisted its execution, and even members on the floor of Congress denounced the law and counselled resistance to it. This served to prevent that harmonious feeling which had been expected from the adoption of the measures of adjustment, and the new fugitive slave act became soon a dead letter from the danger, difficulty and expense attending its execution. Not only was the guaranty contained in the Constitution, and the act of Congress to enforce it, thus rendered nugatory, but for many years slaves had been enticed by agents from the North to make their escape and aid had been furnished them while doing so, under a system which obtained the designation of "The underground railroad." This was not confined to citizens merely but was participated in by state officers who were sworn to support the Constitution of the United States, and instead of compelling their citizens and officers to comply with the Constitution and law, many of the free states passed laws to make it a felony for the owner to arrest his slave or for any one to assist him.