68 RESEARCHES ON DIGESTION DURING THE 18TH CENTURY. [BOOK II. 



The specula- If a specimen of the absurd one-sidedness of certain 

 f Plt " of the followers of tne iatro-mathematical school be 

 sought for, it will be found in the essay of Dr Archibald 

 Pitcairn, in which he sought ' without the assistance of a Daemon or 

 a Stygian Liquor/ to explain gastric digestion as entirely due to the 

 triturating action of the coats of the stomach, the power of whose 

 muscular walls he estimated as equal to 12951 pounds 1 . 



In spite of the writings to which reference has been 

 The views . . f & . ,. ,, 



which pre- made, the opinions of scientific men were altogether 



vailed as to divided on the question of gastric digestion until the 

 gastric diges- middle of the last century. How far the process was 

 tion in the due to foe mechanical movements of the stomach, or 

 ^ e resu ^ f mere maceration, or to any special solvent 

 agent, had yet to be determined, and the solution of 

 these questions had to be obtained by patient observation of, and 

 experiments upon, living creatures. 



The disco- The French naturalist Re'aumur (born 1683, died 

 veriesofR<au- 1757^ after many experiments 2 which had led to nega- 

 tive results, experimented upon a tame buzzard 3 , which, 

 like the hawk, owl, and other birds of prey, regurgitates those parts 

 of its food, such as feathers, bones, &c., which are indigestible. To 

 this bird, Reaumur administered small metallic tubes, containing 

 various articles of food : the tubes were closed at one end and covered 

 by muslin at the other, so as to preclude the possibility of trituration 

 and yet permit of the gastric juice exerting its solvent action. 



When meat was enclosed in the tube it was found to be digested 

 after some hours ; if the period which had elapsed since its intro- 

 duction had not been sufficient, the surface was found softened, whilst 

 the interior remained intact. Not merely was meat capable of com- 

 plete digestion when exposed to the action of gastric juice in 

 these tubes, which protected it from the mechanical action of the 

 stomach, but even bone was softened and dissolved. 



In order to obtain some of the solvent which effected these 

 chemical operations Reaumur placed pieces of sponge in his tubes, 

 and on their rejection was able to obtain from them a fluid of acid 

 reaction, possessed of antiseptic properties, to which he called atten- 



1 The Whole Works of Dr Archibald Pitcairn, &c. Done from the Latin original by 

 George Sewell, M.D. and J. I. Desaguliers, D.D. and F.R.S. 3rd edition. London, 1740. 

 Refer to ' A Dissertation upon the motion which reduces the aliment in the stomach 

 to a form proper for the supply of the blood,' pp. 106 138. Pitcairn was born in 1652 

 and died 1713. In 1691 he was appointed Professor of Medicine in the University of 

 Leyden, an office which he held for a single year in order to return to Scotland, where 

 he became a Professor in the University of Edinburgh. , He is referred to as having 

 been one of the teachers of Boerhaave. 



2 Re'aumur, 'Sur la digestion des oiseaux' (premier memoire), Hern, de VAcad. des 

 Sciences, 1752, p. 266. 



3 Re'aumur, ' Sur la digestion des oiseaux (second me'moire) : De la maniere dont elle 

 se fait dans 1'estomac des oiseaux de proie.' Mem. de VAcad. des Sciences, 1752, 

 p. 461. 



