The Fountain in front is one of the erections of Napoleon, and certainly does no honour to his taste, or that of his architect: a semicircular recess for a shower of rain, with some columns in front, is its best appearance; but usually we see no indication of water, except the green vegetation it produces; and the adjuncts are as poor as the principal object.
The Palais Royal I have already mentioned. The Hotel de Ville has a certain richness of appearance, although it is not in a style of architecture capable of great merit, and even not one of the best examples of the sort. It is, however, as good as our Guildhall.
The Halle aux Blés is justly cited as one of the finest productions of modern art; not for its beauty, to which it has no claim, but for the simple and scientific construction of its noble iron roof; each rib is composed of two bars to form its depth, and a third is added towards the springing. These bars are united by cross bars, radiating from the centre of the circle, and this constitutes the whole of the supporting work; a net of square iron framing rests upon these ribs, and supports the plates of the roof; the diameter of this dome is 142 feet.
Napoleon ordered the erection of several _Abattoirs_, (_i. e._ places for slaughtering cattle, and for the wholesale meat market,) in the outskirts of the city, but within the _barrières_; these are not yet finished; they are very spacious and well disposed, but the one which I visited seemed to be placed too high to admit of a plentiful supply of water. I did not perceive any thing particularly good in the construction, but in the covering there were some experiments which deserve notice. They have used in some parts the Italian semicylindrical tiles, and seem very well satisfied with them, as forming a very light and perfectly water-tight roofing. It is not, however, quite correct to call them semicylindrical, as they are, in fact, the halves of frustra of hollow cones, the lower series being laid with the concave side upwards, and the upper with the concave side downwards, and covering the joints of the lower series. We seem in our pantiles to have aimed at uniting two of these tiles into a serpentine shape, and employing only one series. The chief object of this change arises from the want of a convenient method of fixing the upper tiles. In the _Abattoirs_ these are not fixed, except by the cement, and no inconvenience has resulted in the two years which have elapsed since they were completed. In some cases the rafters are cut into triangular prisms, with the flat side downwards, and the lower tile lies very snugly in the intervals; but for this arrangement, either the tiles must be very large, or the rafters placed very close together. In others the lower tiles were made in the shape of trays, but it was found that the water did not run off as well from the flat surface as from the hollow, and consequently, that a sharper pitch was needful.