418 



SUMMARY OF CURRENT RESEARCHES RELATING TO 



either side of the limb and actuate a lever giving a very smooth and 

 dehcate movement ; a milled-head screw is now provided under the limb 



Fig. 55. 



to put the fine-adjustment out of action when travelling, and thus pre- 

 vents any strain occurring to the mechanical action. The body and 

 limb are mounted on a stage below the trunnions, and the instrument 



