A collapsible and portable rocking chair includes left and right frame side assemblies collectively defining forward and rear leg portions, armrests, and back support members. The integrated circuit is switchable between a master mode of operation, in which a buffer between the first connection and the memory circuit is activated, and a slave mode of operation, in which the buffer between the first connection and the memory circuit is deactivated. The method includes sensing an image of a portion of the surface of the movable member, and calculating a position of the movable member based on the image. The magnet is also strong enough to hold the device securely to the wall so that it projects out orthogonally from the wall surface. Such application-oriented nitride substrates, which can be composed of ternary InxGa1-xN, AlyIn1-yN, AlzGa1-zN, or quaternary AlaInbGa1-a-bN alloy compounds, minimize lattice-mismatch-induced dislocations and defects between the epitaxial films and the substrate on which the device layers are grown, leading to substantially improved device performance. A tube, or bundle of tubes, is placed in the cleaning receptacle, extending through an inlet port from the vertical receptacle, and a gate is closed to clamp the tubes in place.