44 BACTERIOLOGICAL DIAGNOSIS. 
of diagnosis. The former method may be applicable in 
an epidemic of diphtheria, but suspicious throats are 
common and antitoxin expensive. In most cases it is 
necessary to have recourse to the second method. 
Most sanitary authorities have now recognised that 
it is their duty and privilege to provide for the bac- 
terial investigation of supposed diphtheria free of charge 
to doctor and patient, and supply outfits to be used for 
taking the material and transmitting it to the labora- 
tory. When the practitioner lives within easy reach of 
the laboratory (so that the swabs may reach it quickly) 
it is his bounden duty to avail himself of the oppor- 
tunity thus afforded of getting a free opinion from a 
specialist. 
But the case of a practitioner living at a distance is 
somewhat different. Suppose the patient is seen on the 
first day of the illness, an unusual occurrence except in 
an epidenric. The swab is taken, dispatched by post, 
and reaches the laboratory on the second day. It is 
inoculated, and the culture is incubated and examined 
on the third day, the result reaching the practitioner 
about noon on that day. Now the mortality of diph- 
theria which is treated with antitoxin on the first day 
is very small, certainly less than five per cent., while 
the mortality in cases in which its use is not com- 
menced until the third day is much higher, probably 
from ten to fifteen per cent., or even higher. In other 
words, from 5 to 10 patients out of every 100 lose their 
lives if the doctor waits for the result of the bacterio- 
logical examination. It is therefore highly advisable 
that every practitioner should provide himself with a 
bacteriological microscope, and should at least examine 
a film prepared directly from the swab and stained in 
the manner described below. He should also make 
