The People's Conventions, of Ohio and Massachusctts, have des'gnated the 9ih day of August as the day for the great National Convention, to be held at Buffalo, to nominate candi dates for President and Vice President to be supported by the fÃ¯iends of Free Soil, Free Labor and Free Men. We hopo every State wijl rcspond to ihc j cali, and send men, " tried and true," who will come forward with alacrity, and a fÃ¯xed j determination to stand by the principie of j dom. Already the dissenuons growing out of the nominations of the oÃd partios, of men pledg! ed to Slavery and the extensiÃ³n of slave terI ritory, is spreading far and wide. The peoplo have become aroused lo a vindÃcation oÃ their rights, and will no longcr submit to the flagrant encroacliments of slave despotism or the outrages tliat for half a century have been ' ed upon tlie privileges of freemen. The Barnburners of New York have attacked that system of oppression, with an energy ind (letermination that cannot be misunderstood. Thcy liavc unfurted a banner on which is nscribed, Freo Labor, Free Soil and Free Men. T'nder this motto the ranks ihicken, cheered by the exalted enthusiasm of John Van Buren, the master-spirit of that glorious revolution, thev will muve on witli an overwhelm'nop influerce to ihe re=cue of Northern o rights. A cali lias gone forth - thousands will sliout for freedam, as they gather to the standard of Liberty. Already the " Old Bay State" and the Young Lion of the West havo blown the truiÃ¯ipet of freedom, the sound of which has sent a thriil to the hearts of multitudes of freemen, and the echo will be prolonged lili every State frotn Maine to Iowa will give a response to the cal! for united action. There will rio doubt be an immense gatlierÃ¯ng at Bu fÃalo on the 9tk of August. Upon the decisiÃ³n of that Convention rest great results, ! which involve interests of the utmost Ã¯mportance to our country. The public journals give evidence tbat the Liberty party throughont. the various States are identified with this movement. Liberty men, by adherencÃ¼ to principie and integrity of purpose, have been the means of this great revolution. They now have a duty to perform in the crisis which is approaching, and they must prepare to act. The ijuestion is, how shall they act ] This Convention is called without ruference to party, and will nominate a candidate for tlie Presidency. It will be the duty of every Liberty man in attendance to use his for our own norninee. Justice to themselves, to their principies, and justice to Juhn P. Hale, wlio alone so gallantly and fearlessly 6tood by the rights of the Nortli, demands it. We want no letter leader, and we be'.ieve no one will so fully concÃ©ntrate the strengta of the opponents of slavery extensiÃ³n. Manv Liberty men in Ohio and Massachusetts seem to be among the foremost in ihis great movement, and undoubtcdly expect to abide its decisiÃ³n . We are aware that on this sub ject veterans in the Liberty cause will differ; still the questions must be met - must be answered. How are we to do it? Most assuredly not by remaining inactive, and looking with indifference on the great movements which are now agitating our country. No. We must compare sentiments, so as to bring about a eert of action. Tlien let us cali a masa meeting by the first day of August, at Jackson, or some other place designated by the Central Committee. We appeal to them once more to give the cali. Let the information be spread far ind wide, inviting all who adopt the significant violto, to attend ; and let every one come prepared to advance the interests of llie great cause. The sons of the Peninsula State have ever been ready to occupy the van in reform ; and i now !et Micliigan not be the last to respond to the cali of frcedom.