A sharp difference in reports from two observers of the same subject often brings to light a significant phenomenon which may have been overlooked. In the March, 1962, issue of the British Journal of Dermatology, in a paper by Smith et al.,1 it was found in a double-blind study of patients with acne that there was no significant difference between the groups receiving placebo and demethylchlortetracycline. Approximately 20% of the placebo group improved, and 30% of the demethylchlortetracycline. This is contrary to the experience of many careful observers. Hicks2 reported in a double-blind study of acne that 31% of the placebo group improved, whereas 70% of the demethylchlortetracycline group showed significant improvement. Hicks's results are in contrast to those of Smith et al. and more in keeping with the opinion that tetracyclines in a dose of four capsules a day, continued for at least four weeks, probably is