The Croonian Lecture. On the changes the blood undergoes in the act of coagulation

Abstract

After paying a tribute of applause to the talents of Mr. Bauer, as a microscopical observer, the author proceeds to estimate the size of the globules in human blood, 16 of which, when enveloped in their colouring matter, occupy the space of the 160,000th part of a square inch, so that 2,560,000 would be required to cover the super­ficial inch; but when the colouring matter is removed, 25 occupy the 160,000th part of an inch, which gives 4,000,000 to the square inch. The readiness with which the colouring matter is removed by the action of water, and its large relative quantity compared to the globule (being as about 3 to 1), induce the author to believe that the colouring substance is distinct from and not contained in the globules, but that it merely envelops them. The globules of the blood are not of the same appearance in all animals: in the skate they are of an oval form, and about twice as large as those in human blood, and quite independent of the colouring matter. When the globules in the human blood have discharged their co­lour, they coalesce by mutual attraction into various forms, repre­sented in a drawing annexed to the paper. In one instance four globules united so as to form a line with lateral indentations. The author, struck with the analogy between this appearance and that of a single muscular fibre, was induced to request Mr. Bauer to en­deavour to unravel a muscle, so as, if possible, to compare its ulti­mate fibre with the chain of adhering globules. In this attempt he succeeded; and the appearances under the microscope, which were analogous, were given in an annexed drawing. It was further found that by macerating muscular fibre it might be broken down into colourless globules of the same size and appearance as those of the blood.