120 Annual Report for 1893 from the Principal of the 
horse glanders if it were injected beneath the skin, owing to the 
living germs which it contains ; and the next step is therefore to kill 
these germs. This is effected with certainty by exposing the 
unopened flasks to a steam temperature (212° Fahr.) for one hour ; 
but even then the liquid is unsuitable for use, not because it could by 
any means infect a horse with glanders, but because the dead 
glanders bacilli suspended in the liquid are unnecessarily irritating 
when injected beneath the skin. In order to get rid of these dead 
bacilli the turbid liquid is made to pass through a filter of unglazed 
porcelain, and before doing this it is well to add to the liquid car- 
bolic acid in the proportion of 1 : 200. The liquid which exudes 
through the filter is the so called mallein ; it is a perfectly trans- 
parent sherry-coloured liquid, free from even dead germs, but con- 
taining in solution certain chemical substances upon whose presence 
the value of the liquid as an aid to diagnosis depends. 
Fig. 2. 
The appropriate dose for a horse varies in different samples of 
mallein, but of that manufactured in the Research Laboratory 
about 20 drops are usually found sufficient. When it is desired to 
ascertain whether a horse is the subject of glanders or not, the 
above-mentioned dose of mallein is injected beneath the skin of the 
neck ; and during the next fourteen or sixteen hours the temperature 
of the animal is taken every three hours, the changes that ensue at 
the place where the mallein was injected being at the same time 
noted. In healthy or non-glandered horses mallein, in the dose 
mentioned, has no appreciable effect beyond exciting a little 
transient swelling at the seat of injection ; but in a glandered horse 
it provokes a distinct rise of temperature, and in the majority of 
