Before the introduction of a direct method of examining the esophagus, diseases of that organ were diagnosed by inference; and lesions that failed to produce physical signs, altered function or characteristic roentgen appearances, from which the existence of the lesion might be deduced, remained unrecognized. Such was the case with esophageal varices. But with the advent of the esophagoscope, the esophagus was no longer "terra incognita." Every portion of the interior of the organ became accessible to direct examination. This advantage has enabled the discovery and definite diagnosis of many pathologic conditions which, prior to the general use of the esophagoscope, went unsuspected. It permits of a degree of accuracy in the diagnosis of disease that is attained only when the diseased area can be directly inspected. With preliminary roentgenologic study, a diagnosis can be made by the esophagoscope more readily, with greater certainty and with more safety to