GENERAL BACTERIOLOGY 
77 
2. The second dose of such protein may be infinitesi¬ 
mally small. 
3. If the animals do not develop anaphylaxis after the 
second injection, they remain forever immune. 
4. The greatest liability for the development of anaphy¬ 
laxis is between the tenth and fifteenth day after the 
first injection. 
5. Anaphylaxis can be prevented by giving the second 
injection before the tenth day. 
6. Anaphylaxis can be passively transferred from 
mother to her offspring, that is, if mother should be given 
one injection, and her offspring should be injected with 
her blood, and then with an injection of the sensitizing 
substance, the offspring will develop anaphylaxis. 
The experiments of Pearce and Eisenbrey, and par¬ 
ticularly those of Schultz, Dale, and Weil, seem to es¬ 
tablish definitely that the anaphylactic reaction takes 
place not in the blood stream but in the fixed tissue 
cells. 
Practically, the knowledge of anaphylaxis is very im¬ 
portant. 
1. Some diseases can be diagnosed by taking advantage 
of the fact that if a person is unusually sensitive to a 
certain infection because he is infected with it, an in¬ 
jection of a specific bacterial protein will cause a sharp 
reaction and will help diagnose his infection; on this 
principle are based such tests as tuberculin; luetin (for 
syphilis), and mallein (for glanders), Schick’s test, for 
diphtheria; a small amount of specific bacterial protein 
is injected into the skin, and if a person suffers from 
an infection caused by this particular bacterium, a 
marked reaction shows itself both at the site of injec¬ 
tion and in the general condition of the patient. 
2. It explains the mysteries of the so-called “serum- 
