Chicago, April 3. A cali has boon issued by the Hou. J. B. Grinnell, Fltz ILmry Warren, Jacob Butler, üeorgo W. Fiekl, J. 11. "Willituns and a íiumber oí othur prominent Itepublicans ot' tlio Statt: oí Iowa for a rnass conventiou at Davenpoit, on Tuosday, April 2öth, to appoiut delegatos to thu National Liberal Bepablioaii Conventíon at Cincinnati. The cali is addreRsed to thoso citizeus who are opposed to corruption and military supremacy in tho civil admiiiistration. It is proposed to hold also a grand ratificatioa meetiffig at Des Moines aítur the Cinninnati Conventiun.