THE TERRESTRIAL GLOBE AT THE PARIS EXHIBITION.*

Some time before the opening of the Paris Exhibition it was announced that one of the attractions of the show would be a great terrestrial globe, one millionth of the actual size of the earth. The globe is now exhib ited in a building specially erected, near the Eiffel Tower, for the purpose, and it excites the warmest interest among all visitors who have devoted the slightest attention to geographical science. It was designed by MM. Villard and Cotard, and these gentlemen, who have received many congratulations on their success, have lately issued an account of the manner in which their project has been realized.

Maps on a plane surface give, of course, a very inadequate impression of the real appearance of our planet; and ordinary globes are too small to indicate, even vaguely, the extent of the spaces represented on them. The idea of making a globe one millionth the size of the earth deserves, therefore, to be described as a "happy thought," for although the meaning of a million may not be fully appreciated, it is not absolutely inaccessible to the human mind. When we see a place or a district marked on a globe, and learn that the reality is a million times larger, the proportions are impressively suggested, with at least some approach to accuracy.

The diameter of the globe constructed by MM. Villard and Cotard is 12.73 meters, (42 feet). It has a circumference of 40 meters (131 feet), and a millimeter of its surface represents a kilometer (a little more than 153 miles to the inch). The globe consists of an iron frame-work made chiefly of meridians united to a central core. This structure is carried by a pivot resting on an iron support. To the meridians pieces of wood are attached, and on these are fixed the panels composing the surface of the globe. These panels are made of sheets of cardboard bent by hand to the required spherical shape, and covered with plaster specially hardened. Fig. 1 shows how they are applied to the underlying structure. The total surface is divided into forty spindleshaped spaces, the breadth of which at the equator is exactly one meter. Each "spindle" or gore is itself sub-divided, so that there are 600 panels of various dimensions. The designs are painted on the panels before they are put in their place, in order that the globe may ultimately be easily dismantled and removed.

*From Nature, July 18, 1889: vol. XL, pp. 278–280.

The edifice in which the globe is shown has a metallic frame-work forming a cupola. It is lighted from above, and by the great glass frames of the sides. From a terrace or a narrow foot-bridge at the

upper part the visitor can see the polar and temperate regions of the northern hemisphere. As he descends, he is able to see in succession all the regions of the globe to the south pole. At the bottom he comes to the support of the globe with the apparatus for putting it in motion (Fig. 2).

Even the loftiest mountains, if shown in relief, could only have been represented by elevations a few millimeters in height. Consequently the various mountain ranges have been painted on the surface. The various depths of the ocean are indicated in a similar manner.

To facilitate the study of the globe, it has been mounted with its axis vertical, and it may be turned upon the pivot which carries it. If its rotation were made to equal that of the earth, at its equator, a point of

its surface would move at the rate of half a millimeter in the second. This movement would scarcely be visible, but it would, of course, represent an actual movement of the earth over half a kilometer in the same time.

A figure of the moon, corresponding to this one of the earth, would have a diameter of 3.50 meters (113 feet), and would be 384 meters (about a quarter of a mile) distant. A like figure of the sun would have a diameter of 1,400 meters (4,593 feet, or nearly five-sixths of a mile), and be distant about 150 kilometers (93 miles.) The diameter of a globe representing Jupiter on the same scale would be one-half-that of a globe representing Saturn on the same scale would be a little more than onethird-of the height of the Eiffel Tower.

This is not the first occasion on which an attempt has been made to suggest by means of a great globe the size of the earth, and the extent

of its oceans and land masses. The globe of the Château of Marly, which is still to be seen in the National Library of Paris, excited much admiration in the age of Louis XIV, but it has only a diameter of about 5 meters, and is much less effective for its purpose than its successor in the Paris Exhibition.

It is significant of the present state of our knowledge of the interior of Africa that the makers of the globe, in preparing their maps, had twice to alter their representation of that continent in order to indicate the results of the most recent geographical discoveries.