A manual of physiology with practical exercises / by G.N. Stewart.

  • Stewart, G. N. (George Neil), 1860-1930.
Date:
[1898]
Catalogue details

Licence: Public Domain Mark

Credit: A manual of physiology with practical exercises / by G.N. Stewart. Source: Wellcome Collection.

Provider: This material has been provided by the Augustus C. Long Health Sciences Library at Columbia University and Columbia University Libraries/Information Services, through the Medical Heritage Library. The original may be consulted at the the Augustus C. Long Health Sciences Library at Columbia University and Columbia University.

    41/870 (page 33)
    in which red corpuscles are actuall}' destrojed. Destruction of the corpuscles also seems to take place in the spleen and hone-marrow. Although the statement that free blood- pigment exists in the plasma of the splenic vein is incorrect, red corpuscles have been seen in various stages of decom- position within large amceboid cells in the splenic pulp ; and deposits containing iron have been found there and in the red bone-marrow in certain pathological conditions. It is not unlikely that the coloured corpuscles may break up also in other localities, and even to some extent in the blood itself. The lymphocytes are undoubtedh', the coarsely granular oxyphile cells probably, and the hyaline cells possibly, derived from the lymph. The lymphocytes are probabl}' identical with the small lymph-corpuscles, and have little, if any, power of amceboid movement. They are formed largely in the lymphatic glands, for the lymph coming to the glands is much poorer in corpuscles than that which leaves them. The lymphatic glands, however, are not the only seat of formation of leucocytes, for lymph contains some corpuscles before it has passed through any gland; and although a certain number of these may have found their way b}- diapedesis from the blood, others are formed in the diffuse adenoid tissue, or in special collections of it, such as the tonsils, the Peyer's patches and solitary follicles of the intestine, and the splenic corpuscles. To a very small extent white blood- corpuscles may multiply by karyokinesis in the blood. The fate of the leucocytes is even less known than that of the red corpuscles, for they contain no characteristic substance, like the blood-pigment, by which their destruction may be traced. That they are constantly breaking down is certain, for they are constantly being produced. But we do not know whether, under normal conditions, this process takes place exclusively in the blood-plasma or in particular organs or tissues. Physical and Chemical Properties of the Blood. Fresh blood varies in colour, from scarlet in the arteries to purple-red in the veins. It is a somewhat viscid liquid, with a saline taste and a peculiar odour. Its reaction is 3