168 ANALYTIC SECT, XIX, 
solvent power; but at the same time it authorizes 
the conclusion, that its agency is only of second- 
ary importance in the decomposition of aliment 
in the stomach. No more solvent influence can 
justly be ascribed to it in digestion, than what it 
possesses out of the body. Inthe space of eight 
hours, Dr. Stevens dissolved twelve grains of beef 
in half an ounce of gastric juice, exposed to a 
heat of 102°, which may be considered as ‘the 
most successful instance of artificial digestion that 
can be accomplished. It must, therefore, be 
obvious, that if digestion depended solely on the 
gastric juice, the process would not only be tedi- 
ous, but the quantity of it required, would also 
be enormous. As a secretion, however, it. is 
scanty; as a solvent, it requires the co-operation 
of heat. 
ccccxi. As the activity of the gastrie juice 
depends on the degree of heat to which it is 
exposed, all those experiments conducted in tem- 
peratures higher than the blood, cannot be appli- 
cably compared with the digestive process of 
the stomach. 
ccccx1u. The gastric juice is neither acid nor 
alkaline in carnivorous animals, but some trace of 
an acid may usually be detected in that of the 
graminivorous animals. When an acid abounds. 
in the human stomach, it is the product of dis- 
ease, and the digestion is then always weaker than 
