for oscillation about a horizontal axis extending in a plane normal to the axis of the shaft 30 the crank mounting rods 42 are fastened by bracket structures 44 to side bed members 46 of the loom frame the other arms of the double arm cranks 40 extend generally vartically with one extending upwardly and the other downwardly these arms of the cranks 40 are connected by a connecting rod 48 so that oscillation of one crank 40 causes the connecting rods 38 to move up or down in unison and thereby rock the easer bar roller 16 the generally vertical arm of one of the cranks 40 has a connecting rod 50 pivotally connected to the generally horizontally positively reciprocable member 52 of a dobby 54 reciprocation of the member 52 is controlled by the predetermined pattern of the dobby 54 to rock the easer bar roller 16 to decrease or relieve the tension in the warp threads 10 at predetermined intervals for weaving leno type stylized designs although the preferred embodiment described hereinabove contemplates that the leno warp ends will be provided by a singular top beam it is understood that the leno warp ends could be provided by a plurality of top beams or one or more bottom beams regardless of the location of the beam or beams providing the leno warp ends leno warp ends will be contacted and tensioned by the easer bar of the present invention it thus will be seen that the.