432 BOTANICAL GAZETTE [DECEMBER 
Idler pulleys and support.—For adjusting the klinostats to cramped 
positions, or to fixed directions of light, it is often desired to turn a 
driving-belt from a straight course. This has been accomplished by 
means of the shaft and two small pulleys shown standing in the right- 
hand end of the klinostat base in jig. 3, 6. This position of these 
idlers is right for the klinostat to which they are shown attached when 
the klinostat is adjusted for revolution with horizontal axis. For 
other purposes I have had made a cheap iron base into which the 
pulley shaft is set, and this device allows a belt to be turned at right or 
oblique angles anywhere desired. 
Belting and couplings—The belts used are of one-fourth inch 
leather. The thimble-like couplings screw over the ends of the belt 
and hook into one another. Both belting and couplings are common 
articles of trade. 
Shajt-stops—It is often desirable to keep a shaft from working 
out of some position in which it is placed or to prevent it being acci- 
dentally pushed out of position and thus destroying the alignment 
of the pulleys. For this purpose several collars are cut from half- 
inch brass tubing, and each collar is provided with a set-screw. Two 
such collars are shown one above and one below the small pulleys 
on the vertical shaft rising from the base of the klinostat (fig. 3, 9). 
Besides what has been already mentioned there are several things 
which might be added in commendation of this apparatus. It is 
easily portable, in spite of its seeming size. The parts may all be 
screwed to a movable table, or each part may be screwed to a piece of 
plank and the parts then clamped to tables. The shaft supports and 
bearings are easily shifted, placed nearer together or farther apart, S° 
that one may use many shafts of various lengths with any two sup” 
ports. One end of a horizontal shaft may be made to project any 
desired distance beyond a support, and the free end of the shaft may 
support a klinostat or centrifuge plate, thus allowing the plants used 
to be pushed into the recess of a window or into a small, closed 
chamber. The pulleys can be shifted to any position on the shafts, or 
any number of pulleys attached to a single shaft, thus allowing cons 
turn-table driven by that shaft a variety of positions, or allowing 
several turn-tables to be driven from one shaft. The speed of ead 
lution can anywhere be increased or diminished, and a variety of 
