American harbor defense units maintained massive seacoast artillery batteries to protect Manila Bay throughout the early twentieth century. This photograph shows a gun crew executing a loading drill on one of these heavy guns, a labor-intensive process requiring a dozen or more men to ram powder charges and projectiles into the breech. Fortifications like these, built under the Endicott and Taft Board programs, formed the backbone of American coastal defense in the Philippines until their fall during the early months of World War II. Project: 218617