INFECTIOUS DISEASES AND MICROBES, ETC. 249 



sputum (Fig. 48), in the cells of tubercles, and in 

 the blood, 1 tissues, urine, 2 faeces, saliva, 3 and sweat 4 

 of tuberculous patients. Watson Cheyne 5 and 

 other observers believe that the microbe is a spore- 

 producing bacillus ; but this assertion is doubted by 

 Lankester 6 and others. B. tuberculosis has been 

 cultivated artificially, and it has been proved that 

 the strength of its virulence is not lessened by suc- 

 cessive cultivations. When inoculated into various 

 animals it always produces tuberculosis. The pre- 

 sence of this microbe in the sputa of patients sup- 

 posed to be suffering 



from phthisis is a ft-^-* 



certain diagnosis ; 

 and it may be men- 

 tioned that the mi- 

 crobes are most 

 numerous in the 

 small caseous dots 

 contained in the 

 sputa. These dots 

 should be searched 

 for, then crushed 



between two cover glasses, dried, stained, and 

 examined with high powers. 



B. tuberculosis grows on solid blood serum at 37 C. 

 (i.e. the temperature of the body), and in eight 



1 Weichselbaum in Wiener Med. Blatter, 1884. 



2 Bates in Centralblatt fur d. Med. Wissemch., 1883, p. 145. 



3 Griffiths in Proc. Roy. Soc., Edinburgh, vol. xv. p. 44. 



4 Griffiths' Researches on Micro-Organisms, p. 268. 



5 The Practitioner, 1883, p. 248. 

 Nature, 1884. 



FIG. 48. BACILLUS TUBERCULOSIS. 

 A, From human sputum, a, Bacilli, 

 b, Nuclei, x 1500. B, Bacilli, x 435. 



