PART I.] Microscopic Examinations of the Blood in Health. 143 



specially under investigation next, and finally those of various other (ordinary and 

 artificially induced) diseased conditions. 



The methods of examination were precisely the same as those previously employed 

 and described, and consisted in the use of ordinary preparations, preparations which 

 had been exposed to the fumes of osmic acid, and preparations mounted in wax-cells 

 for purposes of continued observation. The microscopic powers employed were the 

 I" and yV" immersion objectives of Ross ; and the ^-^' and ^J' immersion lenses of 

 Powell and Lealand. We have found the ~^' object glass of the latter makers, and 

 the i" of 'Ross, particularly suitable for investigations of this kind, especially when 

 used a im/mersion. 



In connection with the employment of wax-cells in continued observations, 

 renewed experiment was made in regard to their affording the conditions necessary 

 for the development of bacteria or fungal elements, if these were really present. 

 The results agreed with those previously recorded,* preparations of blood inoculated 

 with fluid containing bacteria being quickly decomposed with abundant development 

 of these organisms, and specimens in which one or more of the common atmospheric 

 spores had been enclosed being rapidly dried up by the growth of mycelial filaments, 

 which in many instances produced an abundant crop of their characteristic fructifica- 

 tions. With these preliminary observations we may proceed to a detailed account 

 of our experiments and their results. 



A.— Microscopic examinations of the Blood in Health. 



The following table shows the characters of eighteen specimens of the blood of 

 healthy subjects, the first fourteen being derived from the human subject, the last 

 four from healthy dogs : — 



The features presented in this table, which require special consideration, appear 

 to be the following : the occurrence of echinulation in the red corpuscles, the libera- 

 tion of granular matter from the white ones, the presence of motile points, fibrinous 

 threads and fungi, and finally, the deceptive appearances due to decomposition of the 

 glasses employed in the preparations. 



1. The echinulation of the red corpuscles. — This is a phenomenon which has 

 been so long recognized that it would have been unnecessary to notice it here had 

 not considerable stress been laid upon its presence by various recent writers on 

 pathological histology. We find MM. Coze and Felz describing the red corpuscles 

 presenting " I'aspect d'un chaton de marron d'lnde ; " and appearing " comme recon- 

 verts de piquants qui rappellent tres-bien la forme de batonnets ou Bacteries," as one 



* Eighth Annual Report of the Sanitary Commissioner with the Government of India — Appendix B, 

 p. 154, 1872, and previous pages of this volume. 



Ninth Annual Report of the Sanitary Commissioner with the Government of India- -Appendix A, 

 pp. 37, 38, 1873, and previous pages of this volume. 



