Aparato Respiratorio Y Tuberculosis (9, No. 4, Oct.–Dec. 1944, published in Santiago De Chile) has a paper with the title "La Microscopia Fluorescente En La Investigacion Del Bacilo Tuberculoso" contributed by Dr. B. Juricic, Sr. Nicolás Vuskovic, Drs. Gastón González, Hernán Durán, and Hipólito Vergara. In this they describe the results of their investigation of 5,044 cases in which samples of expectoration and gastric contents over a period of a year and a half were examined by the fluorescence microscope. The accessories utilized for transforming the microscope into a fluorescence type were those manufactured by the Spencer Lens Co., Buffalo, and consist of an electric bulb of low voltage and high amperage, provided with a blue-violet filter, and in addition, of an aluminized mirror with a yellow filter for the eyepiece. A monocular microscope was found more satisfactory than a binocular, the number of prisms in the latter considerably diminishing the fluorescence. The results are shown in two tables and a third supplies comparative figures for the Ziehl-Neelsen method. The advantages of the fluorescence method are obvious from this comparison; 52 per cent greater positive results being obtained than with the Ziehl-Neelsen method. In addition, less time is spent in staining the specimens, there is greater rapidity in the examination, and the use of oil immersion is avoided. It is claimed that the fluorescence microscope has a brilliant future before it and that its efficiency is susceptible of great improvement in various ways.