Peripheral sealing glands for forming a seal between an elongate member and a substantially flat surface are provided. One method includes providing an at least in part frustoconical shaped skirt through which the elongate member is to pass and defining a deformable upper seal configured to deform about and form a first seal to a periphery of the elongate member, providing a flange depending from a lower periphery of the skirt, and providing a substantially rigid ring structured to bear on the outer surface of the flange so as to apply a substantially consistent pressure to the two or more endless lip seals to form a second seal against the flat surface. The skirt includes a retention flange to removably receive the rigid ring and to permit adjustment of the rigid ring relative to the flange.