Description of the Building Committee's Design. The site to have been occupied by the building designed by the Committee was the same as that on which the building has been actually erected, namely between Rotten-row and the drive in Hyde Park, but the area proposed to be covered was somewhat larger, the length of the building being about 2,200 feet, and the greatest width nearly 450 feet. The central space was occupied by an immense rotunda 200 feet in diameter, the cupola rising to a height of more than 160 feet, and exceeding the span of that of St. Peter's at Rome by 61 feet, and of St. Paul's in London by 88 feet. The dome for covering this rotunda consisted of wrought-iron ribs, supporting a covering of corrugated iron, the whole resting on a wall or drum of brickwork, about 60 feet high; a large opening in the centre was to be glazed for the admission of light. This large open area was intended for the exhibition of groups of sculpture, fountains, and other objects requiring great space in order to be seen to advantage; at the same time the cupola would have presented a striking instance of the constructive skill of this country. The remaining area of the building was divided into avenues 48 feet wide, by iron columns 24 feet apart, this dimension having been determined on as that most likely to work in well for the division of the counters and passages. One of the 48-feet avenues on the main axis of the building was spanned by semicircular ribs of wrought iron supporting the roof, which rose here to a greater height than the rest of the building; the other avenues were covered with roofing very similar to that commonly seen in railway-sheds, the whole being rendered as light as possible, and constructed in iron covered with slating; the light being in all cases admitted by a range of sky-lights at the apex of the roof, which was also adapted for ventilation. The height of the main avenue was 52 feet, and of the others 36 feet, from the floor throughout. A corridor of communication 15 feet wide was carried round the whole of the building, interrupted only by the open courts; this, with the main avenue, afforded the visitor to the Exhibition the means of reaching any particular point without threading a maze of small passages. The inclosing walls were to be of brick, relieved externally by panels in two colours; but there were to be no internal division walls except those necessary to surround the various courts which were left on account of the trees.