DIGESTIBILITY OF FOOD. 313 



have recently so far modified the experiments of Spallanzani, who 

 introduced the food enclosed in muslin bags through the gullet into 

 the stomach, as to introduce into the stomachs of dogs, through 

 fistulous openings portions of coagulated white of egg of definite 

 form and definite weight, inclosed in similar muslin bags. This 

 method of procedure, which has been adopted by Bidder and 

 Schmidt, as well as by Buchheim,* may be very advantageously 

 employed in various investigations ; the sole objection to it is that 

 we can only employ extremely small quantities of the substance in 

 question, and that even portions of the same albumen often require 

 very different times for their solution ; this difference appears to 

 depend as much on the varying density of the albumen (which may 

 certainly differ even in one and the same egg), as on the different 

 positions which the bag containing the albumen may happen to 

 assume in the stomach. ^In Buchhe'im's experiments, which were 

 made with cylindrical pieces of albumen weighing 1 gramme (the 

 stomach having been filled three or four hours previously with bread 

 and curdled milk), it was found that in 1 hour sometimes more than 

 59-0-, and in 2 hours even 93 of the originally introduced moist 

 coagulum of albumen were dissolved., although the amount was 

 frequently far smaller. Here again we must give the widest 

 scope to the idea of digestibility ; in 1 hour half of the compact 

 mass of coagulated albumen, which presented comparatively little 

 surface, was dissolved, while the gastric digestion previously took 

 from 3 to 4 hours. Further experiments show us, that far more 

 coagulated albumen is digested in 1 hour in the stomach of a dog, 

 when that organ is empty, or when a long time has elapsed since 

 the last meal was taken, than under opposite conditions, when 

 albumen in small portions, or finely comminuted, is introduced 

 into the stomach than when a cylinder of albumen, of a gramme 

 weight, is introduced, when a freer motion is permitted to the 

 pieces of albumen than was possible when they were inclosed in 

 bags, and lastly, when the experiment is instituted on a perfectly 

 healthy dog than when made on dogs with fistulous openings. 

 Hence we may foresee that large pieces of coagulated albumen and 

 long boiled or more or less dried albumen, must require a compa- 

 ratively long time for their solution, especially when the stomach 

 has been very much filled with food, and digestion has been going 

 on for some time. Hence, independently of many other relations 

 connected with special idiosyncrasies, it is extremely difficult, if 

 not impossible, to find any definite unit of conditions, according to 

 * Beitrage zur Arzneimittellehre. Leipzig, 1849, S, 15-112. 



