The important contribution of Dr. Edward Stevens to the understanding of gastric digestion in man and animals

Herein is presented in larger perspective for the first time a viewpoint proposing the importance of the experimental labors of Edward Stevens in contributing to the solution of the problem of gastric digestion in man and animals. It is contended that the studies of Stevens form a vital and important bridge relating the experimental investigations of Réaumur and Spallanzani. Of the three observers, the celebrated Réaumur first put gastric studies on a more firmly based scientific background. The records of the French Academy, made public in 1752, record two brilliant short contributions by him on digestion in granivorous and carnivorous birds, in the second of which, produced with accuracy and caution, he offers sufficient evidence to show that digestion in these animals (and others possessed of stomach membranes) must be most strongly attributed to the solvent power of the gastric juice. Clearly Stevens confirmed and continued these studies; with him rests the privilege of being the first investigator to isolate the human gastric juice as well as the priority in performing, in vitro, experiments proving the presence in the gastric juice of the active principle necessary for assimilation of food. It was left for Spallanzani to augment and continue these by his stature to ensure finally the scientific studies in masterly and mature fashion and basis for all future gastric studies. One can perhaps no better conclude this account than with Stevens' own final lines in his inaugural presentation, leaving the burden of judgment upon each reader separately to accord or not the wider proposal of acknowledgment which is the intent of this paper. Stevens writes: “In this way we have endeavored to learn by experiments the true cause of the digestion of food and the diverse changes which it constantly undergoes. Let the judgement rest with candid readers as to how successful we have been in this attempt. The difficulty of a short work and the excessive haste with which the limitations of time have compelled us to complete it are the only permissible excuses for the many errors in which it abounds. To have rendered it closer to perfection would have required much more time than is customarily spent in short dissertations of this type. We must, therefore, however defective and weak it may be, submit it to the appraisal of scholars.”