equal to that of the cartridge 201A. While, the third and fourth engaging stubs 108c and 108d (or 112c and 112d) are spaced from the first and second engaging lugs 108a and 108b (or, 112a and 112b) by a distance corresponding to the lateral length of the cartridge 201A or 201C.
In order to put the three cartridges 201A, 201B and 201C into the cartridge holder 101, the following manual work is usually carried out. That is, in case of the cartridges 201A and 201C, as is seen from FIGS. 52 and 53, each cartridge 201A or 201C is thrust at one side edge into the gripping gaps defined by the first and second engaging lugs 108a and 108b (or, 112a and 112b) and then pressed against the innersurface of the lid portion 106 or 107 having the other side edge resiliently engaged with the third and fourth engaging stubs 108c and 108d (or, 112c and 112d). With this, the cartridges 201A and 201C are brought to their held position in the lid portions 106 and 107. In case of the center cartridge 201B, as is seen from FIG. 53, the same is thrust at one side edge into the aligned grooves defined by the two pairs of parallel ridges 102a and 102b formed on the hinge portion 103. With this, the center cartridge 201B is held by the parallel ridges 102a and 102b while standing on the hinge portion 103 with the other side edge directed upward. Then, the two lid portions 106 and 107