ZOOLOGY AND BOTANY, MICROSCOPY, ETC, 
87 
Lead (instead of the radial wheel of fig. 1), which is supported on a 
separate standard and connected with the screw by a Hooke’s joint. 
We believe this plan of providing a separate standard for the milled 
Fig. 1. 
Fig. 2. 
head and actuating the screw by means of a Hooke’s joint was devised 
by Herr Nobert to avoid the tremor of the hand being communicated to 
the micrometer, and yet to utilize this peculiar fine-adjustment acting 
upon the stage. 
