NATURE OF CHYMIFICATION. 337 



a state so homogeneous. This difficulty, however, seems now in a great 

 degree removed, by the discovery of the close Chemical relation that subsists 

 between the various substances of each of the groups already enumerated 

 ( 430) ; which renders it easy to conceive that the changes involved in their 

 reduction may be of a very simple character. 



449. The first series of facts which will be here adduced, as throwing light 

 on the process of chymification, is that which has been obtained by the expe- 

 riments of Dr. Beaumont upon the individual already alluded to (434). By 

 introducing a tube of India-rubber into the empty stomach, he was able to 

 obtain a supply of Gastric Juice whenever he desired it ; for the tube served 

 the purpose of stimulating the follicles to pour forth their secretion, and at the 

 same time conveyed it away. This fluid, of which the existence has been 

 denied by some physiologists, is not very unlike saliva in its appearance ; it 

 is, however, distinctly acid to the taste ; and chemical analysis shows that it 

 contains a considerable proportion of free muriatic acid, and also some acetic 

 acid. The former must evidently be derived from the decomposition of the 

 muriate of soda contained in the blood, the remote source of which is the salt 

 ingested with the food. The latter is an organic compound, probably formed 

 at the expense of some of the saccharine matter of the previous aliment. Of 

 equal importance with the free acids, is an animal matter, soluble in cx>ld 

 water, but insoluble in hot, bearing considerable resemblance to albumen. Of 

 this more will be said hereafter. Besides these principal ingredients, the 

 gastric fluid contains 'muriates and phosphates of potass, soda, magnesia, and 

 lime. It possesses the power of coagulating albumen in an eminent degree ; 

 it is powerfully antiseptic, checking the putrefaction of meat ; and it is effec- 

 tually restorative of healthy action, when applied to old foetid sores and foul 

 ulcerating surfaces. It may be kept for many months, if excluded from the 

 air, without becoming foetid. 



[The most remarkable results of M. Blondlot's investigations* relate to the compo- 

 sition of the gastric fluid, and different as his conclusions may be from those usually 

 received, yet the large quantity of fluid he was enabled to collect in a purer state than 

 any one hitherto has collected it, entitles his account to every consideration. He very 

 carefully distilled on a sand-bath 3875 grains of pure gastric fluid obtained after feeding 

 his dog with raw meat; he repeated the distillation, and repeated the whole experiment, 

 several times, with the gastric fluid of other animals as well as of the same dog, and the 

 constant result was, that the product of the distillation did not once exhibit the slightest 

 acid reaction ; but the residue in the retort was always strongly acid. It was thus proved 

 that the acid of the gastric fluid cannot be either the hydrochloric or the acetic, for both 

 these are volatile at the boiling point of water, and would have distilled over. 



A further proof that it is neither of these nor lactic acid, was furnished by the fact 

 that no effervescence is produced when chalk, marble, or any other carbonate of lime is 

 added to the gastric fluid: and it was this fact which chiefly led M. Blondlot to his con- 

 clusion, that the true and almost only source of the acidity of healthy gastric fluid is the 

 presence of superphosphate and biphosphate of lime. The evidence which he gives in 

 addition to the above is: 1st. There is no acid salt, except this superphosphate of lime 

 which could retain its acidity and remain in contact with carbonate of lime without 

 exciting decomposition; 2d. Sulphuric acid, added to gastric fluid, produces an abundant 

 precipitate of sulphate of lime, and oxalic acid a similar one of oxalate of lime. 3d. 

 Potash, soda, ammonia, and lime-water, produce abundant precipitates of neutral phos- 

 phate of lime. 4th. The calcined ash of gastric fluid was not deliquescent, was dissolved 

 without effervescence by a few drops of hydrochloric acid, with which it formed chloride 

 of calcium; it had, therefore, contained neutral phosphate of lime, the excess of the acid 

 having been decomposed in the calcination. 



The general conclusion of his analysis is, that the gastric fluid is composed of ninety- 

 nine parts of water, with one part of superphosphate of lime, superphosphate of am- 

 monia, chloride of sodium, mucus, an aromatic, and a peculiar principle. Similar 

 results were obtained from the analysis of the gastric fluid of several animals. M. C.] 



450. The Gastric Juice obtained from the stomach, was found by Dr. Beau- 

 mont to possess the power of dissolving various kinds of alimentary substances, 



* Traite Analytique de la Digestion, Paris, 1844. 

 29 



