embodiment illustrated in fig4 a brush seal 52 is mounted in a t shaped slot 60 defined in at least one and preferably each circumferential end of one of the seal ring segments 112 as illustrated the slot extends in a direction that is generally radially with respect to a center of the shaft not shown in fig4 disposed through the seal ring in the illustrated embodiment a seal slot 62 is machined in the circumferential end of the seal ring segment facing the brush to receive the same to provide an additional guarantee of oil sealing under normal operating conditions the two seal ring segments 112 114 contact each other so that no oil flows between them however in the event of sealing malfunction the brush seal is brought into play to seal oil that would otherwise seep between the open seal ring segments as illustrated the brush seal 52 is preferably but is not necessarily mounted to each circumferential end of the upper seal ring segment 112 the brush seals may be installed to the seal ring segment in any one of a number of ways for example with reference to fig5 a gap 64 can be reserved between the metal plate s 56 to which the brush 54 is mounted and the opposing wall s of the t shaped slot or cut out in which the brush seal is disposed a spring mechanism such as a leaf spring 66 can then be disposed between the brush seal and the wall of the slot of the seal ring to urge the brush seal toward the other seal ring segment although in this embodiment one leaf spring is preferably disposed.