OX SOME STRUCTURAL PECULIARITIES OF ORGANISED SUBSTANCES. 367 



however, that the optical properties are situated in those mole- 

 cular groups which we shall henceforth term micellae though 

 standing in no connection with their distance from each other, or 

 with the tensions which they at all times develope between them. 

 Each separate micella acts as a small crystal, and if the effects 

 become added, the resulting interference colour rises the higher 

 the greater the number which the resulting ray of light has to 

 pass, and thus becomes the more intense the greater the number 

 brought to the unit-area of the microscopical image. 



But since organised substances as we shall further on prove 

 consist of a mass of different combinations which mutually com- 

 mingle, and of which each perhaps forms its special micellae, 

 and which also are possibly differently situated ; and since, further, 

 the ratio in which these combinations commingle is, as may be 

 shown, unequal in the different layers ; and since, moreover, the 

 necessity of a constantly equal position does not exist (or at least 

 cannot always be proved) in the lodging of new micellae between 

 those already present though of the like constitution : the 

 transmitted ray is in all probability subjected to the action of 

 differently situated elements, and the ellipse which represents the 

 observed effect can, strictly speaking, be explained only as an 

 imaginary or resulting one, which in regard to form and position 

 is between the real ellipses that act upon the ray. It is, for 

 instance, quite immaterial whether one axis of the ellipse of 

 elasticity is situated radially throughout, or whether in the 

 superposed elements (assuming their number infinitely great) it 

 presents all possible deviations between and 30 to either 

 side, the effect is the same in both cases. Similarly, it is imma- 

 terial whether the successive micellae of the same radial series are 

 situated equally or unequally, in as far as the superposed series 

 only exhibit the deviations just mentioned. We may in general 

 assume any arrangement of the double-refracting elements, pro- 

 vided certain positions, which together produce the observed effect, 

 are preponderantly represented. 



A further peculiarity, which is connected with the inner struc- 

 ture and the method of growth of organised substances, is the 

 unequal fluid-contents of somewhat dense and loose layers, and the 

 inequality of double-refracting power resulting therefrom. Hence 

 it is not permissible to compare transverse sections and surface 

 views, with regard to their double-refracting power, with the 



