3 



STRUCTURE OF GELS 



77 



miniscent of cell. It seems, therefore, that the etymological error is made : 

 to believe that we are deaUng with a barbaric composition of "cellula" and 

 an unknown word beginning with "mi", in much the same way as the 

 word aldehyde is formed." 



By optical means, Ambronn has definetely established the existence of 









o) 



Fig. 59. Former conception of the micellar structure: a) from Nageli and Schwendener 

 (1877), b) from Seifriz (1929) and K. H. Meyer (1930). 



long, submicroscopic particles in gels such as celloidin, denitrated cellulose, 

 celluloid, gelatin, aluminium oxide fibres (see p. 82). These particles often 

 showed an intrinsic double refraction which could only be explained by 

 assuming crystaUine particles (Ambronn, 191 6/1 7). The existence of 

 crystaUine micelles in chitin (Mohring, 1922), in muscle fibres (Stubel, 

 1923) and in vegetable cell walls (Frey, 1926b) was demonstrated by means 

 of the same methods. 



At about the same time the crystalline nature of many colloid particles, 

 for example gold sols, cellulose and many other colloids, was estabhshed by 

 the X-ray method (Scherrer, 1920). Nageli's micellar theory was taken 

 up by Meyer and Mark (1930) and propagated by them among chemists 

 in an almost unaltered form, after having been nursed for a long time in its 

 original form by a few biologists. This is obvious from a comparison of 

 Nageli and Schwendener's scheme (1877) and the model of fibre struc- 

 ture given by Seifriz (1929) and K. H. Meyer (1930): Fig. 59b. In 



