Both sides of the gallery are divided into spaces by pilasters, elevated on a continued zocle or base 5 feet high, forming an order with its entablature 40 feet high, crowned by a vaulted ceiling 20 feet high, divided by radiating archevaults, corresponding with the relative positions of the opposing pilasters, and enclosing deep sunken coffers enriched with paintings.

The spaces between the pilasters are sunk into niches for the reception of the statues of the fathers of the Revolution, contemporary with the immortal Washington; over which are large tablets to receive the National Paintings commemorative of the battle and other scenes of that memorable period. Opposite to the entrance of this gallery, at the extremity of the great circular wall, is the grand niche for the reception of the statue of the "Father of his Country"—elevated on its appropriate pedestal, and designated as principal in the group by its colossal proportions.

This spacious Gallery and Rotunda, which properly may be denominated the "National Pantheon," is lighted in four grand divisions from above, and by its circular form presents each subject decorating it walls in an interesting point of view and with proper effect, as the curiosity is kept up every moment, from the whole room not being presented to the eye at one glance, as in the case of a straight gallery.

Entering the centre pier through an arched way, you pass into a spacious circular area, and ascend with an easy grade, by a railway, to the grand terrace, 75 feet above the base of the Monument. This terrace is 700 feet in circumference, 180 feet wide, enclosed by a colonnaded balustrade, 15 feet high with its base and capping. The circuit of this grand terrace is studded with small temple-formed structures, constituting the cupolas of the lanterns, lighting the Pantheon gallery below; by means of these little temples, from a gallery within, a bird's eye view is had of the statues, &c., below.

Through the base of the great circle of the balustrade are four apertures at the four cardinal points, leading outside of the balustrade, upon the top of the main cornice, where a gallery 6 feet wide and 750 feet in circumference encircles the whole, enclosed by an ornamental guard, forming the crowning member on the top of the tholus of the main cornice of the grand colonnade. Within the thickness of this wall, staircases descend to a lower gallery over the plafond of the proanos of the colonnade lighted from above. This gallery, which extends all round the colonnade, is 20 feet wide—divided into rooms for the records of the monument, works of art, or studios for artists engaged in the service of the Monument. Two other ways communicate with this gallery from below.

In the centre of the grand terrace above described, rises the lofty obelisk shaft of the Monument, 50 feet square at the base, and 500 feet high, diminishing as it rises to its apex, where it is 40 feet square; at the foot of this shaft and on each face project four massive zocles 25 feet high, supporting so many colossal symbolic tripods of victory 20 feet high, surmounted by fascial columns with their symbols of authority. These zocle faces are embellished with inscriptions, which are continued around the entire base of the shaft, and occupy the surface of that part of the shaft between the tripods. On each face of the shaft above this is sculptured the four leading events in General Washington's eventful career, in basso relievo, and above this the shaft is perfectly plain to within 50 feet of its summit, where a simple star is placed, emblematic of the glory which the name of Washington has attained.

To ascend to the summit of the column, the same facilities as below are provided within the shaft, by an easy graded gallery, which may be traversed by a railway, terminating in a circular observatory 20 feet in diameter, around which at the top is a look-out gallery, which opens a prospect all around the horizon.

With reference to the area embraced by the foundations and basement of the Monument and the uses to which they may be applied, the underspace outwards, occupied by the lower terrace and colonnade, may be appropriated to the accommodation of the keepers of the Monument, or those having charge of it and attending on visitors.

These apartments, which are arched, are well lighted and aired, as they are all above ground, the light being disposed in the sunk panels of the stylobate (base). The principal entrance to all these apartments will be from the rear, or opposite side of the portico entrance. The inner space, or that under the grand gallery or Rotundo, may be appropriated to catacombs for the reception of the remains of such distinguished men as the Nation may honor with interment here. This subterranean gallery is so large and lofty that it would accommodate many catacombs.

In the centre of the Monument is placed the tomb of Washington, to receive his remains, should they be removed thither, the descent to which is by a broad flight of steps lighted by the same light which illuminates his statue.