"'Some improvement.' 'Better work than previous year.' 'More effort displayed.' 'Improved wonderfully.' 'Improvement first term, not so much second.' 'Before removal, not transferred; after removal transferred.' 'Very much improved, both mentally and physically.' 'Has made progress.' 'Remarkable improvement.' 'Not transferred before removal, but after.' 'More attentive.' 'A very small but gradual improvement.' 'Am happy to tell you that he is studying more since tonsils and adenoids were removed.' 'Greatly improved.' 'Attention better.' 'More concentration.'" In this experiment like the preceding, the judges are liable to the effect of expectation of improvement. Although the reports are more explicit, they are still couched in general terms, and not commensurable. Some reports refer to intelligence and some to pedagogical standing. There is no control group. On the basis of these results, the author concludes: "Children exhibiting some alternatives in the normal histology of tonsils and adenoids, give marked evidences of mental impairment." This seems to be a rather sweeping statement in consideration of the number of intellectually superior children who suffer from adenoids and diseased tonsils. Another investigation was made by Dr. Cornell in the Philadelphia schools,[12] where seventy more or less retarded pupils in grades one to four were operated on for adenoids. According to the teachers' reports-- 30 per cent improved considerably. 40 per cent improved. 25 per cent did not improve. 1.6 per cent deteriorated. 3.0 per cent deteriorated considerably. Of those who had two chances of promotion, 6.3 per cent were promoted twice. 16.0 per cent failed twice. 33.3 per cent were promoted once. 33.3 per cent failed once. With one opportunity, 11.0 per cent were promoted. 31.7 per cent failed. [12]: Wallin: "Mental Health of the School Child." 1914. "The promotion record was thus decidedly poor. It is possible, however, that the time for promotion came before the orthogenic effects of the operations had become effective." The same criticisms may be brought against this investigation as were mentioned in connection with the preceding ones. Teachers' estimates of improvement, especially when such improvement is expected, and without means of measuring it objectively, are necessarily inaccurate. Again there is no control group. Of even less value are the results of an investigation in New York City by Cronin, where, out of eighty-seven cases operated on for enlarged tonsils and adenoids, "many advanced three grades during the rest of the school year, and only three lost time." An interesting study is one that is described by John C. Simpson, M. D., in the Journal of the American Medical Association, April 1, 1916.