( 963 ) 
The existence of selling crystals is in my opinion one of the 
most remarkable facts which have become known in the study of 
the imbibition phenomena. Ht is certainly very striking that a typical 
erystal with its characteristic optical phenomena and corresponding 
cleavage planes can imbibe water without loss of its crystal nature 
and its homogeneity. But it creates still more surprise to notice that 
all known crystals of polysaccharides or albuminous bodies undergo. 
swelling in water. It does not seem easy to explain how a erystal 
can swell while preserving its crystal nature. But no theory of 
imbibition can be called satisfactory unless it can fully account for 
this fact. The swelling crystals appear to me the touchstone of the 
imbibition theories. 
Next to the amorphous and the crystalline swelling bodies, organic 
nature yields quite a series of products such as starch granules, bark 
fibres, woody fibres ete. which possess no crystal form, but instead, 
an arrangement of particles with corresponding optical EN 
and cleavage planes '). Some investigators have felt inclined ‘f » look 
upon these so-called organised bodies *) as crystals with atypic limt- 
tation planes: others as amorphous substances wherein tensions occur. 
Neither of these two ideas seems to me quite satisfactory. And, provi- 
sionally, I think the best thing is to look upon the organised matters 
as a separate group, being more or less a medium between the 
amorphous and crystalline substances *). 
The analogy between swelling and miaing. 
The fact that a certain analogy exists between the processes of 
swelling and mixing had been already observed by BeERTHOLLET in 
1805. In his “Essai de Statique Chimique” he explains both pro- 
cesses by the same mechanism *‘). The physiologists who have worked 
in the third quarter of the nineteenth century on the subject of 
swelling — I only mention, Cart Lupwie, NAgrni, Reinke — also 
show in their publications in various places that they have noticed 
the existence of that analogy. 
!) Illustrations are given in each test-book of botany. 
2) Amongst the organised bodies must also be reckoned the arisotropous layers 
of grammed muscles. 
5) Whether it is more in particular amongst the organised bodies that the much 
looked for continuity between amorphous and erystalline aggregation condition 
is perhaps to be found, is a question which L can only propound, but not answer. 
Cf. also the facts mentioned by W. Prerrer, Pflansenphysiologie I, p. 69—70, 
4) Compare Vol. 1, p. 34 and 38. 
