216 



DETERMINATION OF TOTAL VOLUME OF BLOOD. [BOOK I. 



then find the amount of blood which the washings contain, which 

 added to the volume of A gives the total volume of blood contained in 

 the body. 



This method may be modified in various ways. Thus the amount 

 of haemoglobin in the fluid may be determined by Preyer's method ; 

 or the tissues and organs may be chopped up finely and treated with 

 water, and the fluid thus obtained after being filtered may be added 

 to the washings from the blood-vessels ; or carbonic oxide may be 

 passed through the blood and through the mixture of blood and water, 

 so as to secure a fluid of more uniform and more persistent tint. 



The following determinations of the relation of volume of blood to 

 weight of body have been made by these methods. 



VOLUME OF BLOOD, EXPEESSED AS A FRACTION OF THE BODY 

 WEIGHT, CONTAINED IN THE BODY OF VARIOUS ANIMALS. 

 (GSCHEIDLEN 1 .) 



Malassez' 

 method. 



It is obvious that by the enumeration of blood 

 corpuscles in blood diluted to a known extent, and in 

 the mixture of blood and washings, the amount of blood contained in 

 an animal's body could also be ascertained, though doubtless not so 

 accurately as by Welcker's method. 



Malassez 2 has actually attempted to determine the total mass of 

 the blood of a living man by the process of enumeration. The 

 number of blood corpuscles contained in a cubic millimetre of blood 

 obtained from the finger having been determined as exactly as 

 possible, 300 cubic centimetres of blood were removed by venesection. 

 Some hours afterwards, the corpuscles in blood again drawn from the 



1 Gscheidlen, Physiologisches Methodik, Dritte Lieferung, p. 337. On this subject 

 consult also 



Gscheidlen, " Studien iiber die Blutmenge." Untersuchungen aus dem physlolog. 

 Laboratorium zu Wurzburg, Vol. n. p. 153 (1869). 



Gscheidlen, " Bemerkungen zu der Welcker 'sch en Methode der Blutbestimmung 

 und der Blutmenge einiger Saugethiere. " Pfliiger's Archiv, Vol. vn. (1873) p. 544. 



Welcker, "Bestimmung der Menge des Korperblutes und der Blutfarbskraft, " &c. 

 Zeitschrift f. rat. Medicin. 3rd Series, Vol. iv. (1858) p. 147. 



2 Malassez, "Recherches sur quelques variations que presente la masse totale du 

 sang." Archives de Phy&iologie normale et pathologique. 2nd series. Vol. n. (1875). 

 Consult especially pp. 277280. 



