245,933. Walker & Son, Ltd., T., Walker, T. S., and Walker, J. Jan. 9, 1925. Logs.-In a log of the submerged type, the housing is in direct communication with a supply of lubricant and the construction of the log is such that lubricant has access through the transmission mechanism to the lowermost bearing of the rotator spindle. The rotator spindle Q is con. tained in a housing 0 which also contains the gearing P by which the rotation of the spindle is transmitted to a flexible shaft J passing through the end cover L of the housing. At its upper end the shaft J carries a member H actuating a make-and-break device C which operates speed and distance indicators A, B. The device C is enclosed in a chamber D fitted with a pressure gauge D' and connected to an oil pump E by a member F provided with a valve G. The spindle Q is formed with a helical groove q or other means serving to convey lubricant to the lowermost bearing of the rotator. In the case of shallow draught vessels an oil tank, having a stop valve, may be connected directly to the upper end of the casing K surrounding the flexible shaft J.