FALSE NETWORKS IN PROTOPLASM 215 



focussed clearly or not ; only the two appearances are rather 

 different. The accompanying diagrammatic figure shows 

 the relations of these two reticular images to one another, 

 the real one (a) in sharp focus, and the optical one (b) 

 with a higher focus. The distinction between them lies in 

 the fact, that the former has a wider and 

 more irregular mesh, the latter, on the 

 other hand, is denser and more regular, 

 appearing in particular more as if striated 

 diagonally. Now if we are able to show 

 that in very fine sections of protoplasm, 

 which have at most the thickness of one 

 or two alveoli, the two different reticular images are actually 

 to be observed, this may perhaps furnish the surest proof that 

 the structure is really present as asserted by me, that is to 

 say, that the meshed structure of the protoplasm depends 

 upon the deposition in it of feebly refracting droplets, which are 

 so crowded together as to form a froth-like structure. Now 

 this is as a matter of fact the case. Both in fine sections 

 through liver cells and elsewhere, I was at an early period 

 struck by this strange phenomenon, without knowing its 

 explanation, and I may well say that at that time it 

 gave me many a mauvais quart d'heure. There can be 

 noticed, as I have said, two reticular images, one with a 

 rather deeper focus, which even at an early period I was 

 able to decide was alone that of the exact focus, and 

 then, a second one which comes into view with a higher 

 focus, and is if anything more distinct than the first one, 

 appearing finer and more striated, and thus corresponding 

 exactly to that which is demanded both by observation upon 

 the oil-foams and by theoretical considerations. 1 



The discovery of the optical reticular images, which I 

 did not make until nearly at the end of my investigations, 

 of course disturbed me very much at first ; indeed for some 

 time I even considered the whole of my views, as to the 

 reticular structure of protoplasm generally, to be entirely 

 exploded, until, as has been described, I gradually found, by 



1 For further remarks on the false reticular image exhibited by protoplasm 

 see the description of sEthalium above, pp. 111-116. 



