Not long ago Rosenberger of Philadelphia came forward with the startling claim that tubercle bacilli are present in the circulating blood even in cases of chronic and localized tuberculosis. The claim was based on the actual demonstration of acid-proof bacilli, which Rosenberger interpreted to be tubercle bacilli, in smears made of centrifugally sedimented blood corpuscles in suspensions of blood in citrate solution. The blood was drawn from a vein at the elbow. Thick smears were used, and after drying the red corpuscles were laked with water.
In view of the practically uniform failure of previous efforts, whether by staining methods or by inoculation in guinea-pigs, to demonstrate tubercle bacilli in the blood in cases of acute and severe febrile tuberculosis, Rosenberger's results were not accepted without reservation. What would the results of other observers, using the same methods as Rosenberger, show? The matter is not settled, but the results already