Za821. Battery Koehler will be a Battery with (8) eight 12 inch mortars. This is 1908 image.
V286. (yPcon-065 77F). Carabao Island runs pretty much on a north-south axis; in this picture we are looking north. Battery Koehler will be a Battery with (8) eight 12 inch mortars. The 8 mortars are placed in two pits with 4 mortars each; they are next to each other. This image shows the northern mortar pit with 4 guns. This picture was shot in the last three months of 1908