When the foregoing requirements of these rules have been complied with, the judge, or clerk, or justice of the peace, as the case may be, shall docket the case in the name of the plaintiff as plaintiff and of the garnishee as defendant; and shall immediately issue a writ of garnishment directed to the garnishee, commanding him to appear before the court out of which the same is issued at or before 10 o'clock a.m. of the Monday next following the expiration of twenty days from the date the writ was served, if the writ is issued out of the district or county court; or the Monday next after the expiration of ten days from the date the writ was served, if the writ is issued out of the justice court. The writ shall command the garnishee to answer under oath upon such return date what, if anything, he is indebted to the defendant, and was when the writ was served, and what effects, if any, of the defendant he has in his possession, and had when such writ was served, and what other persons, if any, within his knowledge, are indebted to the defendant or have effects belonging to him in their possession.