40 APPENDIX, 



smaller than the red, are first effused ; at lost the red globules themselves occasionally 

 escape. It will be seen that this mode of conceiving- the phenomenon does not explain 

 the infinite modifications which the liquids exhaled into the inflamed parts undergo. 



Mr. Fodera notices cases in which the lymphatics or thoracic duct have been said to 

 contain different substances, which had been introduced either into the digestive ca- 

 nal, the serous cavities, or into the cellular tissue. If the effects of absorption are not 

 manifested, in the experiments, where a portion of intestine, containing poison, has no 

 longer any communication with the rest of the body, except by a lymphatic vessel, we 

 must seek for a cause in the extreme slowness of the circulation of the lymph. M. Fo- 

 dera inserted some liquid prussiate of potass in the subcutaneous cellular tissue of the 

 thigh and abdomen of two young rabbits. In the first animal, at the expiration of a few 

 minutes, and in the second, at the end of half an hour, he found it in the lymph of the 

 thoracic duct, in the urine, the mucous of the intestines, the synovia, the s'ermn of the 

 blood, the serosity of the pericardium, of the pleura, and of the peritoneum, as well as 

 in all the solid parts, except in the crystalline lens, the cerebral substance, the interior 

 of the nerves, and the ossous tissue. In another experiment the interior of the nerves 

 presented traces of it. 



Would not these experiments tend to prove that absorption in these cases had ta 

 ken place at tbe same time, both by the lympatica and blood-vessels ? 



While the German physiologists have ascribed absorption to the absorbents and veins 

 only, Messrs. Magendie and Fodera have extended this function to the arteries also. In 

 this, however, we think that they have been misled by fallacies which had crept into 

 then- experiments, and especially by the unnatural position and deranged actions which 

 the operations and agents required by the experiments induce in the animal and in the 

 parts experimented on. From every consideration we are led lo infer, that the infer- 

 ences at which Tiedemann, Gmelin, and Mayer have arrived, approach the nearest to 

 truth. 



The experiments performed by Darwin, and more recently by Wollaston, Brande, 

 and Marcet, tend to prove that different substances introduced into the stomach are 

 found mixed with the urine, without having passed by the lymphatic or blood-vessels. 



Fodera has repeated these experiments, and made them undergo an ingenious 

 modification, which has discovered to him phenomena unobserved by former physiolo- 

 gists. He introduced into the bladder a plugged catheter, after having tied the penis in 

 order to prevent the urine from flowing along the sides of the sound. He laid bare the 

 oesophagus at the anterior part of the neck, and injected into the stomach a solution 

 containing some grains of the ferruretted hydrocyanate of potass. This being done, 

 he frequently removed the plug, and received on filtering paper the urine which es- 

 caped. On this paper he dropped a solution of sulphate of iron, and added to it a little 

 hydrochloric acid in order to destroy the color. In one experiment the prussiate was 

 detected in the urine ten minutes after its injection into the stomach, and in another 

 live minutes afterwards. The animals were opened immediately. The salt was found 

 5n the serum of the blood taken from thethorac portion of the vena eava inferior, in the 

 right and left cavities of the heart, in the aorta, the thoracic duct, the mesenteric 

 glands, the kidnies, the joints, and the mucous membrane of the bronchia:. 



This important experiment proves the extreme rapidity of absorption ; it shows also 

 that the prussiate of potass found in the urine, is conveyed thither by the ordinary cir- 

 culating ways. 



The following experiment demonstrates the rapidity of pulmonary absorption in par- 

 ticular. Fodera opened the thorax of a rabbit, and removed the heart, immediate- 

 ly after some prussiate of potass had been injected into the trachea. This operation was 

 performed in twenty seconds : the interior of the left auricle, however, presented a 

 bluish green colour, which was more deep at the mitral valve and les apparent in the 

 aorta. The absorption, therefore, seems to take place at the very instant when the in- 

 jection has penetrated into the subdivisions of the bronchia. 



We are of opinion, that to limit the process of absorption in every part of the body, 

 and under every combination of circumstances to which it is subject, to one particular 

 process, or to one particular conformation or property which the vessels, whether blood- 

 vessels, or others, may possess, would in the present state of our knowledge, be to 

 draw an inference not' justified by many important facts. On the contrary, it seems more 

 probable that not only the vital properties, but those of a physical nature, are requisite 

 to the production of "the phenomena in question; and that the Jatter set of properties 

 are under the control of the former. 



Instead of attempting to show that those physical properties for which Messrs. Magen- 

 die and Fodera have contended, are not to a certain degree efficient in the production of 

 the process in question, \ve would only argue for their subordinate character, which may 



