274 The Physiology of Plants BOOK in 



of the action of capillarity, pointing out that the sinking of 

 such a water column as is presented by a vessel, would 

 in consequence of evaporation be greater than the raising 

 of the liquid due to the capillary attraction of the cell 

 wall. He then claimed that the imbibition of the cell wall 

 on which Sachs laid so much stress is only a special case 

 of capillary action. His theory of the action of the living 

 cells was based upon the occurrence of such cells in imme- 

 diate contact with the vessels at intervals along their 

 course. Such cells obtaining water by endosmosis from 

 those abutting on them would cause an infiltration into 

 the vessels in the same way as the original infiltration into 

 the vessels of the root. This infiltration he supposed to 

 be intermittent, so that air and water would pass into the 

 vessel alternately, giving rise to the Jamin's chain. We 

 have thus the view of osmotic forces of some intensity 

 occurring at various heights in a tree, and coming into active 

 play in the living cells in the neighbourhood of vessels 

 and tracheids. These living cells he held to be especially 

 the wood-parenchyma and the medullary rays. This view 

 had been suggested, though in a cruder form, by Grew in 

 his Anatomy of Plants (1682), p. 126. 



Godlewski put forward the same views as Westermaier 

 in 1884, and they received energetic support from many 

 other writers, and especially from Janse in 1887, and 

 Schwendener in 1892. 



On the other hand they were opposed very strongly by 

 Strasburger, who came to diametrically opposite conclusions 

 in consequence of his own researches in 1891. The experi- 

 ments he carried out present very formidable obstacles to 

 the living-cell theory, for he showed that liquid can be 

 raised to heights greater than that of the barometric column 

 in cut stems, in which the living elements have been killed. 

 Strasburger killed the tissues in the stems he experimented 

 with in some cases by boiling them, and in others by 



