CHICAGO, Aug. 16.—The communists of this city are making active preparations for a somewhat warlike campaign. The fact has been developed that they have purchased a large number of breech-loading muskets, with considerable ammunition, and are drilling regularly under command of experienced Prussian officers. Several hundred men are already enrolled, and picnics are frequently held to raise funds to defray expenses. The leaders are the same discontented spirits who have previously figured in communist mobs, and they seem very much determined to redress the imaginary wrongs under which they are laboring.—Evening News.