66o 



LABORATORY EXERCISES 



system can be rotated from the vertical to the horizontal position by pulling out the 

 spring catch E, Fig. 234. 



Fig. 234— Details"of Edinger's drawing apparatus. Z. Drawing board- T micro- 

 scopic attachment; K, and K2 condensers; L. electric lamp attachment. 



For photomicrographic work a camera .is clamped to the pUlar 5 Fig 234 the 

 plate holder, which will take plates of any size up to 24 by 30 cm., resting on the 



