Still another fallacy in the comparison of incidence in institutions and the like is proven by the work done by Jordan, Reed and Fink, who found that in the various Chicago telephone exchanges the attack rate varied from five per cent. to twenty-seven per cent., although the working conditions were approximately the same. The attack rate in one section of the students’ army training corps in Chicago was 3.9 per cent., while in another section particularly exposed to infection it was 39.8 per cent. Similarly Frost found the incidence in Louisville, Kentucky, to be 15 per cent., and in San Antonio, Texas, 53.3 per cent. All these figures show the difficulty of comparing rates for various institutions and various groups of individuals. Although Fishberg quoted Rickmann in support of his contention that influenza has no effect whatever upon tuberculosis, Amberson and Peters used his work in support of their contention, and call attention to the fact that in thirty out of forty tuberculous persons reported by him who had contracted the grip, the attack did not produce any aggravation of the lung condition. Presumably it did in the other ten. If even 25 per cent. of tuberculous patients who contract influenza have their pulmonary condition aggravated, this should be regarded as a notable number. According to Stivelman, 11.4 per cent. of tuberculous influenza cases died at Montefiore Home. In a survey of convalescents from the Loomis Sanatorium, Amberson and Peters found that seventy had contracted influenza, or 5.7 per cent. of the number surveyed, and that 11.4 per cent. of these had had relapses of their pulmonary condition, apparently due to the acute disease, while 22.9 per cent. had died from the intercurrent infection. 2.8 per cent. were deaths due to tuberculosis after convalescence from the influenza. Tubercle bacilli have been found in the sputa of convalescent grip patients, whose sputa had previously been negative, by Amberson and Peters, as well as by Berghoff, at Camp Grant. The latter found that 50 per cent. of his cases showed a reactivation and a positive sputum after an attack of influenza. Amberson and Peters agree with Fishberg in the observation that there has been no increase in the general mortality from tuberculosis within the recent months, and suggest as an explanation the possibility that during the epidemic enough of the old cases were carried off to account for a temporary lull until new cases developed, or others had time to reach later stages of the disease. As we have previously remarked, Leichtenstern observed this same phenomenon following the 1889–1890 epidemic.