17,1 Smith: Complement Fixation for Syphilis 85 
On the strength of these results we adopted the ice-box Was- 
sermann, using the simple alcoholic extract of beef heart an- 
tigen as our routine test at the New York Post-Graduate Medical 
School and Hospital. When I visited there in August of last 
year it was still giving excellent satisfaction. 
The routine Wassermann reaction.done in the laboratories 
of the New York City Department of Health is the ice-box test, ' 
using the simple alcoholic extract antigen. The value of fixation 
at ice-box temperature was pointed out in New York City as 
early as 1912, by Dr. Archibald McNeil, then of the Depart- 
ment of Health. O. Berghausen* has recently commented on 
the superiority of ice-box fixation. He has adopted it as routine 
in his laboratory. E. H. Ruediger* has lately made rather ex- 
tensive studies of the relation of temperature to complement- 
fixation. He endorses ice-box fixation. 
It is my belief that incubation at 8° C., or thereabouts, for 
from four to twenty-four hours, and the use of two antigens, 
one a simple alcoholic extract and the other a cholesterinized 
extract, makes a very much more sensitive test and also a far 
more reliable test than that which is ordinarily done. In known 
syphilitics the reaction with the cholesterinized antigen may be 
used as a guide to treatment. In a diagnostic test the reaction 
with the simple alcoholic extract antigen may be relied upon. 
In closing, let me add that, no matter how delicate the reac- 
tion nor how reliable or specific it may be reputed to be, one 
should never diagnose syphilis on a single positive Wassermann 
reaction alone. Keep the patient under observation and under 
suspicion. Go over him again and again. Look especially to. 
his aortic arch. Have the test repeated. Have it done, if pos- 
sible, by the ice-box method with a simple alcoholic extract an- 
tigen. If it is then positive you may feel justified in putting 
your patient upon antiluetic treatment. 
* Journ. Am. Med. Assoc. (1919). 
‘Journ. Inf. Dis., two recent contributions. 
