PLATE VI {continued) 



Fig. 5. 56-5°. 



Fig. 6. 68-2°. 



Fig. 7. 90° (flat spiral). 



X-ray diagrams of spirals constructed using filaments of well-oriented artificial 



silk. Each spiral was less than 0-5 mm. diameter and therefore lay within the 



X-ray beam. The angles given are those between the filament and the spiral axis. 



Spiral axis parallel to long edge of page. 



