for the gun to be mounted on a top carriage. The guns at d d are on siege carriages.

128. Subsequently the order was modified to put one 100-pounder Parrott and two 30-pounders into position, instead of three 30-pounders, and, finally, batteries were built for guns as above described, Fig. 2, Plate VI, represents a cross-section, and Fig. 3 a longitudinal section, of the surgery.

129. Plate VII represents these batteries on an enlarged scale, Fig. 1 shows all four batteries together; Fig. 2 is a section of a b of Fig. 1; Fig. 3 is a section of c d, Fig. 1; Fig. 4 is is the magazine and the right of the covered way; Fig. 7 represents the method of taking the 100-pounder gun across the marsh; i is a side view and k an end elevation.

130. The 30-punders were taken from the ordinance yard on Morris Island in a small scow, and mounted on siege carriages without limbers, and were afterward drawn across the marsh about 150 yards, in the dead of night, in a heavy storm of rain.

131. The roadway across the marsh was made by throwing down a layer of brush, say, 3 feet deep; on this, which was well trampled down, were placed transversely 1-inch boards, which were the best that could be obtained, and longitudinally over these were 3-inch planks, for the wheels to run upon.

132. The 100-pounder gun was taken farther up the creek to the right, and having been provided with a wooden cylinder secured around the cone of he chase by iron hoops, after the manner of stars, and corresponding in diameter with the re-enforce, was parbuckled and rolled over the marsh on two thick planks.

133. Some difficulties having occurred with the iron carriages used with the Parrott rifle gun, but more particularly as there were fewer of them in the department than were required for use, and as the commanding general desired to fire these guns at a higher angle of elevation than the authorized carriages admitted of, two experimental carriages were made, which are represented in Plate XIII.

134. The object of these carriages being to admit the use of high degrees of angles of elevation, the top carriage was so made that the whole rear of the gun, including the re-enforce, passed between the side cheeks, the cabscabel clearing the rear transom of the top carriage.

135. They were made of the common hard pine of the country, hewed in the woods. These carriages worked well, and possessed the advantage of being easily made. Any engineer company can construct them in almost any part of the southern department, from material found in the country, excepting a few iron bolts and threonine planters, which were easily made at the portable forge. I think they will be found as good or better than the authorized iron gun carriage.

136. A modification of this plan is used at Black Island for a 100-pounder gun at the right batteries. The only difference consists in an eccentric shaft being used with the top carriage. This carriage is represented in Plate XIV.

137. They have not yet been sufficiently tested to determine their value, but everything indicates durability and sufficient strength. The carriage represented in Plante XIII requires roller handspikes to maneuver it, but is otherwise more simple than that represented in Plate XIV.

138. The batteries on Black Island having been constructed for