Vice-President’s Address. 23 
of tuberculosis, the same will apply to those cases in which, 
by Koch’s treatment, we may succeed in localising the 
tuberculous process. Two difficulties present themselves, 
which doubtless in time, however, will be removed, but 
which at present deserve our most careful attention. It will 
be necessary to make sure that the process of death, localisa- 
tion, and separation of the dead mass are complete, and even 
when this is the case, the greatest care will have to be 
exercised in the removal of these necrosed masses, so that the 
sequestrum and its contents may be disturbed as little as 
possible. Free but careful incision will have to be the rule 
in Cealing with these dead and separated tuberculous masses; 
and it is probable that in making these incisions the thermo- 
cautery may be called into greater and greater requisition. 
What, too, if the localisation is not complete, or if the 
healthier tissues will not react to the specific poison, or if they 
are over-stimulated, will there not be greater danger than 
before of the tubercle spreading ? 
It would be idle with the data at our disposal to attempt 
to discuss the nature of the lymph, but, so far as we can 
see, it is some preparation of the secretions of the tubercle 
bacillus, considerable support being given to this view by 
the fact that the local and constitutional reactions are not 
set up in other cases where we have granulation tissue 
somewhat similar to tuberculous tissues, as in syphilis for 
example, from which we must assume that the lymph 
does not necessarily act on all tissues of low vitality. 
Koch’s lymph, acting in conjunction with the products of the 
tubercle bacilli in the body in the bringing about of rapid 
disintegration of the cells amongst which they lie, is probably 
of the same nature as the poison developed in the body, com- 
pelling the activity of the tubercle poison to be exerted at 
once on the cellular tissues, probably by a kind of cumulative 
effect, so as not to allow of its being transferred by lymphatic 
or other channels even of those tissues in the immediate 
neighbourhood of the sequestrum. It may be that, acting on 
the healthy tissues, it assists in setting up rapid localised 
reactionary changes, by which are brought up a sufficient 
number of active cells and fluids to deal with any bacilli that 
