136 



after another period of six hours, was very bitter. On the 28th the 

 fluid had evaporated down to a thick honey consistence. 



The next remark on this subject, in the author's rough notes 

 taken at the time, is the following : 



January 27. "The honey solution is now nearly evaporated. A 

 mass of crystals (grape-sugar) with a small quantity of syrup, in- 

 tensely bitter." The syrup could be reridily poured off from the 

 crystals. The mucous membrane was not in the slightest degree 

 decomposed ; swelled and elastic, not splitting into layers. 



It is well known that, after long keeping, granules of grape-sugar 

 are found in honey ; therefore, on the 22nd of April, the honey from 

 which the experiments were made was re-examined, and found to be 

 nearly homogeneous and not separated into crystals and syrup ; 

 indeed the whole physical appearances are so different from the 

 honey after being operated upon, that the author cannot doubt the 

 influence of the membrane in effecting the changes registered. 



At this stage of the inquiry an important doubt suggested itself. 

 In the above experiments no small importance has been attached to 

 the circumstance of bitterness becoming developed in the various 

 solutions when kept in contact with the membrane. In every case 

 indeed the membrane was washed with jealous care, but the fact is 

 palpable, that it is almost impossible to divest the membrane of 

 every trace of bitterness ; when this is effected as far as practicable, 

 in a very few minutes the damp membrane increases perceptibly in 

 bitterness. When washed, submitted to pressure between folds of 

 blotting-paper, stretched out on a board and dried as rapidly as 

 possible in a current of warm air, it is still bitter. May not the 

 bitterness alluded to in the above cases be attributed to disintegra- 

 tion of the mucous membrane itself? The following experiments 

 seemed sufficiently simple in their conditions and adapted to answer 

 the query. A body was selected in which well-known molecular 

 disturbances are easily established cane-sugar. 



Sugar. December 28. A portion of membrane was covered with 

 a solution of white sugar ; another portion, of the same size, was 

 covered with lukewarm water, and both were exposed to a tempera- 

 ture of 32 C. One hour having elapsed, the watery solution was 

 just perceptibly bitter, the saccharine solution decidedly so. 



December 29. The watery solution was rendered very slightly 



