
Figure 11.--Flight chamber for studying moth aerodynamics. (a) Roa battery; 
(ob) circuit (fig. 5); (c) A 15M selenium cell; (d) connection of strobe light; 
(e) across relay contacts of the Sigma 11f, 1000-ohm relay of circuit (fig. 5). 

15 
Figure 12.--White- 
lined sphinx ina 
banking turn. The 
low-intensity red 
light beam crosses 
from the right and 
focuses on A 15M cell 
at left. Although 
the light intensity 
is low, the strobe 
fired even though 
the cell was partial- 
ly blocked by an 
arctiid. Because 
the cell operates at 
low light levels, 
the camera shutter 
is left open and the 
film does not be- 
come fogged. The 
strobe light alone 
takes the picture. 
(Callahan, 1964). 
