Detroit, July 3, 1848. Friend Hussey : Ãn considering wliat course of action it was appropriate for us to adopt. at this most favorable juncture in the Anti-Slavery cause, it was my purpose to speak of tlie more obvious meane for advancing its principies, as proclaimed and advocated by the Liberty party, rather than to discuss the question which is now becoming deeply important in the minds of many of our friends, (particulary in Massachusetts and Ohio,) whether the time had not arrived whan, without the sacrifice of principie, there might not be a uniÃ³n among all the Anti-Slavery men, of whatever political creed, and a new organization effected by which multitudes hitherto standing aloof from the Liberty party, will be brought heartily to co-operate in the advancement of our principies. Already immense gatherings of the friends of liberty and free soil havo been heldin both ofthose States, attended by leading men of all parties, who were prepared to sacrifice all other distinctive party principies and unite on sorae common platform to roll on the cause of human liberty, and at both of these moetings a cali was issued for a grand rally of the friends of" Free Soil and Free Principies," to be held early in August at the city of Buifalo. What may grow out of these mass movements that may jusdfy the friends of liberty n securing their co-operation forthe advancement of our great principies, it is as yet impossible to determine, and useless to speculate, as the events will soon be upon us. For one I can say there mustbe a coming up to a much higher standard of abolition principies than the Barnburning Democracy of New York have yet given us in the recent elabÃ³rate letter of their dislinguished nominee, (Van Buren,) before I could look with the least favor upon united action. This might answer for the New York Tribune stamp of Anti-SIavery men, but I trust it will not take with any who have long 6nce adopted higher ground than the mere question of slavery extensiÃ³n. And yet I am free to say, that if there can be some course of united action adopted and recommended at that Convention, which, while it shall secure all the fundamental principies of the Liberty party touching the abolition of Slavery, will, by a re-organization to some extent of that party, securehe immediate and hearty co-operation of thousands throughout the free States, who have hilherto acted with the Whig-and Democratie parties, I shall rejoice to seo it. But, be that as it may, the means which as Liberty men we shoulÃ¡ now seek to use to the best possible advantage, and which I would especially recommend, may be summed up in this - " agÃtate !" - by means of Anti-SIavery periodicals, parnphlets, speeches, and to keep the pubIiÃ¼ nxÃnÃÃ ariiflui Ua awaku to tlio abominations of Slavery, and its cont rolling influence upon the morÃ¡is, politics and prosperity of our enUre land ; to the shameful, humiliating fact thal our would-be great men are soen crouchingto the haughty demands of the slaveholder, and suiFering liberty to lie prostrate and bleeding even in the Senate Chamber of the Union as witnessed in the Oregon debate, when but two voices were heard in her defence, or basely turning their backs upon all the cherished principies and peculiar interests of the North, as evidenced by the recent shameful bids of Northern aipiranls for slaveholding suffrages, and the unprincipled action of both Whig and Democratie National conventions. These are no longer matters of 6peculation or mere idle declamation, but shamefui, veritable facts, forraing a part of the recorded history of our country which no political demagogueism can gainsay or refute, enacted, too, with such bold eÃFrontery as lo awaken the attention of every reflecting candid mind. Now with these facts out before the natiun, it does seem as if all that Anti-Slavery men need to do was to spread them far and wide, by means oftheir numerous organs throughout the land, and press them upon the attention oftheir fellow citizens. Surely at such a time as this, when the Anti-Slavery presa is teeming with such stirring trulhs, calculated to arouse the sleeping sensibilices of the North and awaken them to aclion, no Liberty or Anti-Slavery man should be destitute of at least one thorough Anti Slavery organ, and, where at all practicable two or three, published in different parts of the land, will be found of great service in furnishing lum with facts and argumenta with which to meet his Pro-Slavery opponents. In connection witli the spread of Anti-Slavery documents, speeches, &c, vve may urge the holding of town and village meetings of the Anti-Slavery friends, inviting and urging the attendance of friends and neighbors of any and every political faith, to talk over with them the great and stirring truths and principies we seek to advance. We are satisfied lar more good can be accomplished in this way, for the advancement of our cause where the Anti-Slavery friends will mingle together and depend upon their own domestic, or neigliborhood efforts, in a spirit of kindness and candor to reason with their fellow citizens, than by any great effort or system at State agency or foreign lectures. A file of the " National Era," (an excellent paper,) by running back over the past six months would furnish facts and arguments enough to give a power to the weakest advocate of our cause, which all the subliity of the wisest Pro-Slavery political opponent could not overthrow. We are persuaded that frequent meetings of that kind amongour friends scattered over the State could not fail to produce the happiest rcsults, and bo found among the most eflective means to advance the cause of liberty. But should any of them feel that greater good could be done by the assistance of others, I may state that our well known friend, Honry Bibbj the " eloquent fugitivo," is now in this city, where he will probably spend most of the summer, and I am authorized from him to say that although he does not court such service at present, yet if the friends in any portion of the State think a visit from him would be of service to the cause, and will raise the necessary means to defray his expenses, and some reasonable compensation, he will cheerfu'.ly answer their cali. Any Communications addrossed to him here will be duly received. In connection with other means I would also cheerfully second your suggestion, that our State Executive Committee arrange for calling one or more mass meetings of all the friends of Liberty throughout the State, to be held at such place and time as they, after duo inquiry shall deem best for the good of our common cause. It seems to me that these and kindred means vigorously adopted and urged by our friends throughout the Peninsular State, can not but result in advancing the great principies.