After a debate of four months Congress admitted California as a free State as one of five compromises. Jefferson Davis, however, repudiated the idea of advantage to his section. He said: "Where is the concession to the South? Is it in the admission, as a state, of California, from which we have been excluded by congressional agitation? Is it in the announcement that slavery does not and is not to exist in the remaining territories of New Mexico and California? Is it in denying the title of Texas to one half of her territory?" He held that gold washing and mining was particularly adapted to slave labor, as was agriculture that depended on irrigation.[32] The day after the admission certain southern senators sent to that body a _Protest_ against the injustice of the act of Congress, admitting California as a free State. The Senate refused the clerk permission either to read or record it. Whereupon the newspapers began publishing articles of severe criticism and talked of dividing the Union. Jefferson Davis went before the United States Senate and, addressing it, called attention to these comments, adding that so much outside criticism was doing more to divide the Union than the _Protest_ would possibly do. Congress finally voted that the _Protest_ be recorded.[33] Was this to be a free State in every sense of the word? This was the day when the slave power "was covertly grasping at the Spanish-speaking countries beyond the Rio Grande, as it had at the lands beyond the Sabine."[34] At first, it was not, for a good many slaves were brought into the State. On April 1, 1850, an advertisement appeared in the _Jackson Mississippian_ referring to _California, the Southern Slave Colony_ and inviting citizens of slave-holding States, wishing to go to California, to send their names, number of slaves, time of contemplated departure, etc., to the _Southern Slave Colony_, of Jackson, Mississippi. The design was to settle in the richest parts of the State and to secure an uninterrupted enjoyment of slave property. The colony was to comprise about 5,000 white persons and 10,000 slaves. Another effort to extend slavery in this section came in the unsuccessful filibustering expedition of the Tennessee lawyer, William Walker, who undertook to establish to the south in Sonora, a State with a constitution like that of Louisiana, basing his advocacy of slavery on the lofty grounds of civilizing the blacks and liberating the whites from manual labor. To explain the meaning of this expedition Bancroft considers it sufficient to point out that Jefferson Davis was Secretary of War at that time and that the Gadsden purchase was then under consideration.[35] In 1852 Peachy of San Joaquin introduced a resolution to allow fifty southern families to immigrate into California with their slaves. Some of them came without permission but on finding that they could not legally hold their slaves, they sent a part of them back while others became free.