Report on the progress of human anatomy and physiology in the year 1843-4 / [Sir James Paget].

  • James Paget
Date:
1845
Catalogue details

Licence: Public Domain Mark

Credit: Report on the progress of human anatomy and physiology in the year 1843-4 / [Sir James Paget]. Source: Wellcome Collection.

    34/66 (page 34)
    Absorption by blood-vessels.* * * § The experiments of MM. Flandin and Dangerf confirm the general rule of the absorption of poisons from the digestive canal, by the branches of the vena portae. Hence they are all found in large quantities, and some exclusively, in the liver. Their latest examinations were made on the absorption of the salts of lead, which they detected in the digestive canal, the liver, spleen, kidneys, and lungs : but not in the blood, heart, brain, muscles, or bones. Lead differs from copper in that its salts after absorption may pass off with the urine. Experiments, by Oesterlen,t have also proved that mercury in its crude state is capable of being freely absorbed and circulated with the blood. It may be ab¬ sorbed by the skin with the aid of friction, or from the intestinal canal. After absorption from the walls of the abdomen or the digestive canal, minute particles of it are found, for the most part, in the spleen, liver, and kidneys: and it is espe¬ cially through the last two organs (at least in cats) that that which is absorbed is subsequently discharged. Globules of it have also been found in the saliva of a woman in whom it had been long applied in friction: and they existed in still greater number, (mixed, as in the saliva, with epithelium) in her urine. In one case mercury, absorbed in its metallic state, produced pneumonia with depots of pus, apparently like that which ensues when mercury has been injected into the blood-vessels of dogs. Mr G. Robinson,§ continuing the experiments alluded to in the last Report, and varying! them/ has shown that when a stream of water is made to flow through a flaccid membranous tube perforated by numerous small apertures, it will exercise a force like that of absorption upon a fluid external to the tube. Under favorable circumstances some of the fluid outside the tube is drawn into it and carried on with the current that is flowing through it. [The results of such experiments, ingenious as they are, cannot be safely admitted to prove more than that the circulation is necessary to absorption by blood-vessels, and that flaccid vessels and a rapid stream are favorable to it, by permitting imbibition and by carrying off the imbibed fluid as fast as it can enter. In the small veins and the capillaries near them the current of blood is not rapid ; but, as already said, its rate is only about an inch per minute in the latter, and 1 -8th faster in the former. The drawing power of such a current must be incalculably small; and its effects are, visibly, so minute that a part of the blood in every small vessel adheres to the internal surface of the wall, the adhesion between them being greater than the force of the current can overcome. It is, therefore, not imaginable that the same force should be capable of overcoming the powerful capillary attraction of the fluids held in the pores of the walls of the vessels. It is only when these fluids, by mixing with the still layer, have passed through it into the central current, that they are carried on with the blood.] * I use this term rather than absorption by veins, because there is no doubt that this kind of ab¬ sorption takes place through the coats of all blood-vessels that are not too thick, although, of course, the absorbed fluids are usually detected only in the veins. j: Report from the Academie des Sciences, Jan. 29, 1844, in the Gazette Med.Fevr. 3, 1844. But in an extract from some journal in the Oesterreichische medic. Wochenschr., Mai 25, 1844, a Prof. Cozzi is said to have detected “ a salt and oxyde of lead combined with the albumen of the blood of a pa¬ tient suffering from lead-colic. ± Oest. Medic. Wochenschrift, Fevr. 24, 1844; from Roser und Wunderlich’s Archiv, Heft iv, 1843.