112 COMMISSIONERS OF INLAND FISHERIES. 



the upper to the lower portions of the paddle shaft by means of a 

 sliding sleeve, which is pinned to the upper shaft through a slot. 

 When the sleeve is raised up the paddle is disengaged. Thus each 

 paddle may be operated separately without interfering with the 

 entire machinery. 



With the exception of the paddle shaft and the transverse shaft 

 running across the houseboat, the entire shafting in use consists of 

 one-inch round steel shafting supported by ordinary babbited shaft- 

 hangers and pillow blocks. It is very necessary to use shaft as light as 

 one-inch because in the long drives (at present about 530 feet — 250 

 feet on each side of the houseboat) and the constant bending of the 

 long floats, caused by the motion of the waves, a heavier shaft be- 

 cause of its rigidity, would pull out the hangers. The one-inch 

 shafting readily bends with the float and the low speed (18 R. P. 

 M. in the longitudinal shafts) is not materially interfered with. 



Between each raft unit the shafting is connected by a sleeve 

 coupling so devised that by sliding it back the shafting on the farther 

 unit is disengaged. In this way the power on each unit raft can be 

 stopped independently. Furthermore, since these couplings are loose 

 on the shafts, they permit the shafts of two adjacent units to slightly 

 pull apart or come together under stress of the bending caused by the 

 waves without materially interfering with the alignment of the shaft 

 or the transmitted power. 



The constant bending of the rafts led to an attempt to install 

 electric motors on each unit. In such an arrangement, each unit 

 would be independent of all others, and slack wires would easily 

 take up all changes in length between rafts due to this motion. A 

 practical method of installing a motor was easily found and tried out, 

 but under present conditions proved to be too expensive. 



4. CONSTRUCTION AND CARE OF THE REARING BOXES. 



Previous to 1908, large bags made of canvas or scrim were used in 

 rearing lobsters. Since this time wooden boxes have been substi- 

 tuted and have been found to be more satisfactory in every way. 

 Even at their best the canvas bags were not as efficient as the cars, 



