546 



Illuminated reflector 



.ri: 



Rigid vertical qirder 



/ 



Box model 



-C 



Bubbli 



Camera 



Plan View of Box Model and Comero 



Reference mark 



Framework supporting 

 charge ,.^ 



^. 



Bubble 



Target 

 plate 



\y\j^ 



Vertical 

 girder 



Elevation of Box Model Viewed from Comera 



Fig I PLAN AND ELEVATION OF BOX MODEL AND 

 CAMERA ADJUSTMENT 



