496 International Exhibitions. [Oct., 



sides, and the entire structure may be said to consist of a series of 

 concentric rings arranged around a central garden. In the middle 

 of this garden is a small circular domed building, containing a 

 collection of all the standard weights and measures of different 

 countries ; and at the boundary of this garden, and inside the inner 

 circle of the Exhibition building, is a covered piazza which formed 

 a favourite lounge for visitors. Around the inner circle are 

 arranged, concentrically, a series of galleries, or arcades, of varying 

 dimensions, intersected radially by sixteen avenues leading from the 

 outer to the inner circles, and a second covered piazza runs round 

 the outside ring of the building. All the inner galleries are lighted 

 from the roof, but the covering of the outside gallery, which rises 

 to a height considerably above the rest of the building, is unpierced, 

 light beinsj furnished to it bv a row of clerestory windows on either 

 side surrounding the entire birilding at an elevation above the roofs 

 of the adjoining galleries. The inner galleries which contain the 

 Fine Arts court, and the History of Works Museum are built of 

 solid masonry, with roofs of iron and glass of no great span. The 

 intermediate galleries consist of light trussed wrought-iron roofs, 

 supported on hollow cast-iron columns, and en the apex of each 

 roof is a skylight, by which the gallery below is lighted. This 

 portion of the building in no way enters into composition with the 

 articles exhibited, and, with the exception of the roof, it may, for 

 all practical purposes of effect, be said to have disappeared. The 

 great exterior circle, or nave, is 110 feet wide and nearly 82 feet 

 high in the centre : the pillars supporting it, of which there are 

 86 pairs, are each 83 feet 6 inches in height, and 62 feet 10 inches 

 to the springing of the arched roof. In this gallery machinery 

 was principally exhibited, and in its centre a raised platform, sup- 

 ported on cast-iron columns, extends right round the building in an 

 unbroken line, excepting where it is intersected by the grand 

 avenue, from either side of which it is approached by a flight of 

 steps. The columns supporting this promenade served also to 

 carry the shafting by means of which motion was communicated 

 to the machinery. 



This great zone has an outside diameter of about 1,550 feet 

 lengthways, and 1,250 feet across, and contains an area of upwards 

 of 11 acres, whilst the entire Exhibition building, with the central 

 garden, occupies a space of about 35 acres. It would be impossible, 

 however, to state the actual area of the space occupied for the pur- 

 poses of exhibition, for all the surrounding park, having an area of 

 about 70 acres, is studded all over with annexes and other buildings 

 erected by the many exhibitors who could not obtain space within 

 the main building. Besides the general annexes there have been 

 erected in this park lighthouses, theatres, a club, churches, various 

 manufactories for glass-blowing and cutting, baking, washing, &e. &c, 



