DIGESTION. 249 



chemistry to physiology, and to afford a scientific explanation of the 

 animal processes, it has been believed that the digestive process, 

 sooner than any other, would be more or less elucidated by these 

 means. Every one recollects that the iatro-chemical school based 

 a great part of their philosophy on the facts which they believed that 

 they knew regarding the digestive process. Since then scarcely any 

 department of the physiology of vegetative life has been made the 

 subject of such brilliant scientific labours as the digestive process. 

 It is needless to name the great work of Tiedemann and Gmelin, 

 for even to the present day we constantly find in this rich treasury 

 of admirable observations, fresh motives to new^experiments and 

 to new views ; witness the numerous meritorious investigations 

 which have been pursued in the Giessen laboratory, on the chem- 

 istry of the juices, and of the materials on which they act. The 

 barbarous experimental physiology of the French created new ways 

 and means, in order to penetrate into the obscure mystery of the 

 digestive process. The very names of Blondlot and Cl. Bernard 

 are indelibly associated with the ideas of well-directed vivisections, 

 performed with extraordinary dexterity. Science had scarcely had 

 time to rejoice over the admirable monograph of Frerichs (written 

 under the superintendence of Wagner) when reports reached us of 

 wonderful discoveries emanating from the Dorpat laboratory, and 

 throwing an unexpected light on many points connected with the 

 digestive process. 



But if, in such a department as this, where we seem to be deal- 

 ing with the most direct actions of chemical forces, we are obliged 

 to admit that the results which to-day we appear to have obtained 

 by the most direct experiment and the most positive observation, 

 are to-morrow rendered doubtful by other experiments and other 

 observations, we should, at all events, learn to exercise caution in 

 expressing our opinion even on apparently the most exact observa- 

 tions. Did it not appear to be an established fact that lactic acid 

 is always present in the gastric juice ? and yet, in many cases, 

 C. Schmidt has demonstrated its absence and the presence of free 

 hydrochloric acid ; and even at the present time does not Blondlot 

 still retain his earlier view regarding the presence of acid phos- 

 phate of lime in this fluid ? Who could expect that after Bernard's 

 most recent experiments on the influence of the pneumogastric 

 nerves on gastric digestion, their influence would be disproved, or, 

 at all events, rendered questionable by the most positive experi- 

 ments? When fat is brought in contact with the pancreatic juice, 

 French observers recognise its immediate disintegration into fatty 



