MOVEMENTS OF IRRITATION. 



455 



carries a movable brass triangle which, as is seen from the 

 drawing, can be firmly fixed against the rim of the flower-pot, 

 which is thus rendered immovable. 



If now an object, say a pot plant, is to be rotated, we proceed 



Fig. 148. 



Fig. 110. 



Fig. 150. 



Fig. 151. Fig. 152. 



FIGS. 148-152. Wortmann's clinostat with attachments. 



as follows. The pot is first introduced into the support Z, and 

 fixed by means of the triangles, this operation being completed in 

 less than a minute. The pot support is now fixed on to the shaft 

 / by means of the set screw, and set in rotation by a twist of 

 the hand (say against the pin h, from which the weight i must 

 previously have been removed). If now the flower-pot has been 



