"The second instance is this. In the spring of 1848, plans were prepared for the erection of an ornamental glass structure, to cover the conservatory wall at Chatsworth. This wall was previously a plain flued structure, devoted to the growth of rare and choice plants. The new erection is 331 feet in length, and 7 feet in width. It is divided into ten bays, with an ornamental centre projecting beyond the general line of the building. Each bay is subdivided by smaller bays, which are separated by glass pilasters; the glass sashes are so arranged that they can be removed in summer, and the whole thrown open to the gardens, whilst in winter the building affords an extensive promenade under cover. The ground on which this structure is built has a fall of 25 feet 6 inches in its whole length; consequently, there is a proportionate fall at each bay, which gives great variety, and obviates the monotony that would be exhibited in a building of such length and dimensions placed on a uniform level. The lower side of each bay is finished by a glass pilaster, three feet in width, and surmounted by a vase on the wall behind. The roof is on the ridge-and-furrow principle, with the rafters on a very slight inclination; and the ventilation is effected in a similar but more perfect manner than that already described as in use at the conservatory at Darley Dale. "The new Victoria Regia House, which presents a light and novel appearance, is 60 feet 6 inches in length, and 46 feet 9 inches in breadth. Although, when compared with the Great Industrial Building, the Victoria House is a very diminutive structure, yet the principles on which it is constructed are the same, and may be carried out to an almost unlimited extent. The form of the roof, the general elevation, the supports, and the mode of construction, are all quite simple, and yet fully answer the purposes for which they were intended. [Illustration: INTERIOR OF VICTORIA REGIA HOUSE.] "The Victoria House, however, was so built as to retain as much moisture and heat as possible, and yet to afford a strong and bright light at all seasons; whilst, on the contrary, the Industrial Building, being intended to accommodate a daily assemblage of many thousands of individuals, and a vast number of natural and mechanical productions, many of which would be destroyed by moisture and heat, is constructed so as fully to answer that end." This, then, was the experience which enabled Mr. Paxton to conceive his design for the "Crystal Palace," a description of which as it has subsequently been carried out we must now proceed with. General Description of the Building.