To the Editor:
In your answer to the question as to the relative merits of the present intradermal method of vaccination, and its advantages over the old scratch method (The Journal, January 17, p. 223), you failed to mention that one of the chief advantages of the intradermal method is that it gives a much higher percentage of "takes" than vaccination by the so-called "incision" method. This point I (The Journal, Aug. 24, 1918, p. 654) proved rather conclusively as a result of a comparative study of the intradermal and "incision" methods at the time that I devised my original method of intradermal vaccination against smallpox. In my method I injected 0.1 c.c. of virus diluted with equal parts of sterile distilled water. Zinsser also makes note of this point in his most recent textbook of bacteriology (Hiss-Zinsser: A Textbook of Bacteriology, Ed. 5, 1923, p. 899). T. Twyman (J.