128 ON THE ELEMENTARY PARTS OF THE HUMAN FABRIC. 



147. In speaking of the Chemical constitution of the Red Corpuscles of 

 Blood, it is necessary to distinguish the substance of their walls and nuclei 

 from their fluid contents. These may be separated by treating them with 

 water ; which, as already mentioned, occasions the rupture of the cells, the 

 walls of which sink to the bottom, whilst their contents are diffused through 

 the liquid. The substance obtained from the former has been termed Globu- 

 line; but it does not seem to differ in any essential character from other sub- 

 stances, that result from the organization of the proteine-compounds. The 

 compound which forms the contents of the red corpuscles, however, and 

 which gives them their characteristic hue, is very different both in its sensi- 

 ble properties, and in its composition; and has received the designation of 

 Hsematine. When separated from albuminous matter, it is of a dark-brown 

 hue, and is tasteless and insoluble in water, alcohol, and ether ; but it is rea- 

 dily soluble in water or alcohol, that contains alkalies or acids ; whence it may 

 be supposed to unite with these, like albumen, as an acid or a base. In 

 composition, however, it differs considerably from that of the proteine-com- 

 pounds; its formula being 44 C, 22 H, 3 N, 6 O, with a single proportional 

 of iron. When burned, it yields a notable quantity of peroxide of iron ; and 

 one atom of this is considered to be present in combination with each equiva- 

 lent of the animal compound. The red colour is not due, however, as for- 

 merly supposed, to the presence of this peroxide ; for M. Scherer has proved, 

 that the metal may be entirely dissolved away by the agency of acids, and 

 that the animal matter, afterwards boiled in alcohol, colours the spirit intensely 

 red. On the other hand, the iron is most certainly united firmly with the 

 constituents of the Haematine, as contained in the red corpuscles ; for this sub- 

 stance may be digested in dilute sulphuric or muriatic acid for several days, 

 without the least diminution in the quantity of iron, the usual amount of which 

 may be obtained by combustion from the Hsematine that has been subjected 

 to this treatment. When diffused through water, in the manner just describ- 

 ed, the Haematine exhibits the same changes of colour under the influence of 

 oxygen, acids, saline matter, &c., as the Blood undergoes in similar circum- 

 stances. 



148. The question of the origin of the red Blood-corpuscles is a very inte- 

 resting one, and cannot yet be regarded as completely determined. That they 

 are to be regarded as nucleated cells, conformable in general character with the 

 isolated cells, which constitute the whole of the simplest Plants ( 125), and 

 having each an independent life of its own, the duration of which is limited, 

 there can now be no reasonable doubt. From this we should infer that they 

 have the power of reproducing themselves ; and the recent observations of 

 Dr. Barry and other Microscopists seem to confirm the statement long ago 

 made to that effect by Leeuwenhoek. The first change said to take place, is 

 the appearance of delicate radiating lines between the nucleus and the peri- 

 phery ; dividing the disc into several segments, usually six in number (Plate I., 

 Fig. 22.) The margin is soon observed to become crenated, by indentations 

 at corresponding points ; and these indentations become deeper, until a com- 

 plete separation takes place, setting free six young cells or discs (a, 6, c, d, e), 

 which seem to have been formed around the margin of the nucleus of the pa- 

 rent cell. Between the small newly-generated disc, and the full-sized corpus- 

 cle, we should expect to find every intermediate size ; and this is affirmed by 

 these observers to be the case. It has been lately asserted by Dr. G. O. Rees, 

 that, when examining a portion of Blood maintained at about its natural tem- 

 perature, he observed some of the corpuscles to assume an hour-glass form, 

 by a contraction across their middle ; and that, by the increase of this contrac- 

 tion, producing the complete division of the corpuscles, two unequal-sized 

 circular bodies were eventually produced from each ; which, when treated 



