A tubbing lining for a tunnel or shaft is formed from tubbing rings having annular end surfaces, with successively tubbing rings are aligned with each other at annular end surfaces forming an annular joint. The toner for developing electrostatic latent image has a number average molecular weight in a range of from 10,000 to 30,000 and a ratio of a Z average molecular weight and a weight average molecular weight in a range of from 3. A second bypass line extends from circuit between the exterior exchanger and accumulator to accumulator, and is operably coupled to second exchanger.