56 



THE AMERICAN MONTHLY 



[March, 



etpath. du Sang, Paris, 18Y8, p. 44) 

 has recently affirmed that in chronic 

 ansemic conditions he has measured 

 them as larpje as 12 or even 14 

 micromillimeters (the latter=r551- 

 milHonths of an inch) and as small 

 as 2.5, or even 2.2 micromillimeters 

 (the latter= SG-millionths of an inch). 

 But even taking the limits I had 

 myself measured as the extremes 

 for healthy individuals, the differ- 

 ence in size between the largest and 

 the smallest human blood-corpuscle 

 was about as great, relatively, as 

 the difference between the shortest 

 and the tallest adult" man, and as 

 in both cases all possible transition 

 f orais occur, I held that by measur- 

 ing ten, hfty, or a hundred, or even 

 a much larger number of corpuscles, 

 we are no more likely to obtain an 

 average size that will agree with 

 the next set of similar measure- 

 ments, than we are by measuring 

 the height of as many men, likely 

 to obtain an average which will 

 agree with the average height of as 

 many more individuals measured 

 elsewhere. It was to this cause, 

 chieliy, that I attributed the con- 

 siderable differences between the 

 statements as to the average size of 

 human red corpuscles, published by 

 the highest microscopical authori- 

 ties during the last few years. I 

 said that while many English and 

 American microscopists continued 

 to assume the infallibility of the 

 alleged average size of 312-mil- 

 lionths (rsV^) of a,n inch, propound- 

 ed by G-ulliver in 1848, such able 

 French microscopists as Cornil and 

 Kanvier {Manuel d^IIistologie Pa- 

 thologique, Part II, Paris, 1873, 

 p. 498), placed it as low as 7 

 micromillimeters {i. e. 275-mil- 

 lionths or xsVs" of an inch). The 

 commission of the French Societe 

 de Medecine Legale (Annates d ''Hy- 

 giene Puhlique, T. 40, 1873, p. 

 194) composed of Messrs. Miahle, 



Mayet, Lefort and Cornil, which 

 reported June 9th, 1873, placed it 

 at 7.5 micromillimeters ((i. e. 295- 

 millionths, or -^-^ of an inch), with 

 which Hayem (p. 43 o]9. cit. supra) 

 and other recent French authorities 

 agree. On the other hand, J. 

 Pelouze and E. Fremy {Traite de 

 Chimie, etc., 3^"" ed. entierement 

 refondue, t. YI, Paris, 1865, p. 

 492) place the average as high as 

 Y^^ of a millimeter {i. e , 328-mil- 

 lionths or -^^^^ of an inch), while 

 the average usually acceijted in 

 Germany, that of Welker [Zeitseher. 

 fur Rat. Med., Bd. XX, 1863, S. 

 237), is intermediate between the 

 foregoing, viz. : 7.74 micromilli- 

 meters (i. e., 304-milhonth8 or -g^V? 

 of an inch). 



" As for myself, I did not pretend 

 to make any general statement as 

 to the true average size of the hu- 

 man red corpuscles, my experience 

 being that the averages obtained 

 by the most careful measurements 

 of any moderate number of cor- 

 puscles differ considerably. As to 

 this I cited the figures I have pub- 

 lished {Amer. Jour, of Med. Sci., 

 January, 1875, p. 1 ; and Trans, of 

 the Amer. Med. Ass., Vol. 27, 1876, 

 p. 304), and added that several other 

 averages of measurements of human 

 blood recently made by me with 

 every possible precaution, also dif- 

 fer from each other considerably 

 (as will be seen below). 



" As for the red blood-corpuscles 

 of the dog, I testified that I had 

 measured in this animal single cor- 

 puscles as large as the largest I have 

 ever myself measured in human 

 blood ; others as small as the small- 

 est in human blood, and every pos- 

 sible transition between. Here, too, 

 in taking averages I had arrived at 

 variable results, as Gulliver himself 

 did long ago. I explicitly stated 

 that the general average of all the 

 measurements that I ever recorded 



