MOLECULAR CONflGURA IION OF NUCLEIC ACIDS 



1.7 A 



3.4 A 



* 



:-> 



i » 



• 



vx^ 



>-v 



/ 



Fig. 6. X-ray pattern of microcrystallinc fibres of DNA. The general intensity dis- 

 tribution is similar to that in Fig. 4 but the diffraction is split into sharp reflections 

 owing to the regular arrangement of the molecules in the crystals. Sharp reflections 

 extend to spacings as small as 1.7 A. (Photograph with N. Chard; DNA by L. D. 



Hamilton.) 



s-44 



