276 



<^3^ JAOaGS lx7a.V 



LOW ^ELOCI'n- 



Fig. 5 

 Wooden Cupola 



Fig. 7 

 Metal Cupola — Cap is too low; outflow 

 of air is choked down 



Fig. 6 



Metal Cupola — Cap is too high; wind 



and rain blow in 



Fig. 8 

 Metal Cupola with Storm Band 



Fig. 9 

 James Solid Hood Ventilator 



Fig. 10 

 James Revolving Hood Ventilator 



