Many physicians believe that hemorrhages from peptic ulcer are rarely fatal. The potential dangers of this condition, therefore, are not fully appreciated. If one concludes, from his individual experience, that gross hemorrhage from peptic ulcer is rarely or never fatal, one is likely to offer a good prognosis, adopt a laissez faire policy and wait for the bleeding to stop. The records of pathologists, coroners and large city hospitals, however, show that the mortality of this complication is much higher than is generally believed. For the purpose of arriving at a better understanding concerning the management of these patients, a study was made at the San Francisco Hospital of the 1,025 entries of 890 patients with peptic ulcer, from Jan. 1, 1928, to Dec. 31, 1934. Three hundred and forty-nine patients (38 per cent) entered the hospital because of gross hemorrhage from peptic ulcer1or developed this complication during the