36 Proceedings of Royal Boeiety of Edinburgh. [dec. 5 , 
it appears that the most important problems requiring' the attention 
of the pathological worker are — (1) To isolate the microbes and 
their alkaloids in a given contagious disease, and to study their 
chemical and pathological actions ; (2) To destroy the microbes (if 
they reside in the blood) in situ by hypodermic injections of some 
germicide. 
II. Cellulose the Prohuct formed by certain Micro- 
Organisms. 
In the Journal of the Chemical Society [Trans.], 1886, p. 432, 
Mr Adrian J. Brown, F.C.S., describes an acetic ferment, called 
by him Bacterium xylinum, which forms cellulose ; the substance 
of the membranous growth of the so-called “ vinegar-plant,” or the 
“ Essighautchen ” of Dr Zopf. 
In my previous paper on this subject (loc. cit.) I alluded to the 
fact that Dr E. Freund had discovered that Bacillus tuberculosis 
forms cellulose. My own work on this micro-organism (to be 
described in this present memoir) entirely confirms Freund’s dis- 
covery, and somewhat extends his observations. He found cellulose 
in the organs and blood of tuberculous persons, and I may add that 
cellulose is also to be found in the sputa of patients suffering from 
acute general phthisis. This was proved by the reactions used by 
Freund (see Nature^ vol. xxxiv. p. 581) for the detection of cellu- 
lose in tuberculosis. 
Ill, Action op Certain Antiseptics and Disinfectants upon 
VARIOUS Micro-Organisms. 
I have already shown that a solution of salicylic acid is a germi- 
cidal agent of a large number of micro-organisms j and at this point 
I wish to detail several experiments undertaken to see the action of 
various reagents upon the life-histories of certain microbes. 
(a) Sarcina lutea. 
Several Aitken’s tubes (fig. 2) containing sterilised beef-broth 
(neutral) were taken and treated as follows : — 
Tube No. I. was inoculated with the chromogenic saprophyte 
Sarcina lutea (from a pure cultivation in nutrient agar-agar), and 
