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have been in one of his irritable moods. He will have none of 

 Spallanzani. The article, of course, shows his intimate knowledge of 

 comparative anatomy. He even says : — " The stomach appears not 

 only to be capable of generating an acid, but air, the latter in 

 disease." He speculates as to the blood being the source of this air. 

 He " is inclined to suppose an acid in gastric juice as a component or 

 essential part of it." He tested it with syrup of violets, which 

 became red. Gastric juice coagulates milk and white of egg. " It is 

 not the digestive power which coagulates milk, complete coagulation 

 takes place even where digestion does not at all go on." This is a 

 remarkably shrewd observation, in view of what we now know 

 regarding pepsin and rennin. He records the fact that, while 

 stationed at Belleisle, he introduced worms into the stomachs of 

 animals, and observed the effects of heat and cold on the process of 

 digestion. 



To complete the story, perhaps the best way will be to quote 

 Senebier's Life of Spallanzani : — 



" Some experiments made by Spallanzani upon digestion, for the purpose of his 

 lectures, induced him to study this obscure process. He repeated Reaumur's experiments 

 on gallinaceous birds, and he observed that, in this case, trituration is an end, without 

 being the means, of digestion. He found the gizzard of those animals, which pulverizes 

 walnuts and filberts, and even lancets and needles, does not digest the pulverized 

 matter ; that it must undergo a new preparation in the stomach, in order to form the 

 alimentary pulp which contains the elements of the blood and of all the humours. He 

 evinces that digestion is effected in the stomach of a multitude of different kinds of 

 animals — insects excepted — by the action of a juice which dissolves the aliment; and, 

 to render this demonstration more striking, he had the courage to make experiments on 

 himself, which might have proved fatal to him, and address to complete his proofs by 

 artificial digestions executed on his table in glass vessels, wherein he mixed the aliments 

 with the gastric juice of animals, which he knew how to extract from their stomachs. 

 But this book, so original, from the multiplicity of the experiments and observations 

 which it contains, is still more deserving of attention from the philosophic spirit which 

 dictates it. This work gave offence to John Hunter. I know not the cause of his 

 displeasure. In 1786 he published his Observations on certain parts of the Animal 

 Economy, in which he discharges some piercing shafts against Spallanzani, who avenged 

 himself by publishing the work in Italian, and addressing to Caldani, in 1788, Una 

 Lettera apologetica in riposta alle osservazioni del signor Giovanni Hunter, in which he 

 repels, in a tone of moderation, but with an irresistible strength of reasoning, the 

 affected disdain of the Engish physiologist, and demonstrates his errors so as to leave 

 him no hope of a reply." (J. Senebier, in Memoirs on Respiration by Spallanzani . 

 Trans. 1804.) 



" Spallanzani was about the middle size ; his gait was lofty and firm ; his counte- 

 nance dark and pensive. He had a high forehead, lively black eyes, a brown complexion, 

 and a robust frame. He had never experienced, during his whole life, but one fever." 

 (J. Senebier.) 



