in HOW BEST TO MODEL THE EARTH 63 



permit of the details being studied. It is therefore 

 proposed that the globe should rotate on its polar axis, 

 by which means every part of the surface would be 

 accessible, by choosing the proper point on the platform and 

 waiting till the rotation brought the place in question 

 opposite the observer. But as such an enormous mass 

 could only be rotated very slowly, and even more slowly 

 brought to rest, this process would evidently involve much 

 delay and considerable cost. Again, as the facility of 

 producing accurate maps by photography is one of the 

 most important uses which the globe would serve, it is 

 clear that the spiral platform, with its balustrade and 

 supporting columns, would interfere with the view of any 

 considerable portion of the surface. To obviate this 

 difficulty it is stated that arrangements will be made by 

 which every portion of the spiral platform may be easily 

 raised up or displaced, so as to leave a considerable 

 portion of the globe's surface open to view without any 

 intervening obstruction. In order that this removal of a 

 portion of the roadway may not shut off access to all parts 

 of the globe above the opening, eight separate staircases 

 are to be provided by means of which the ascent from the 

 bottom to the top of the globe may be made. 



Objections to the Plan of M. Eeclus. 



This account of the great earth-model proposed by M. 

 Reclus clearly indicates the difficulties and complexities in 

 the way of its realisation. We are required to erect, not 

 one globe, but two, the outer one, to serve mainly as a 

 cover for the real globe, being very much larger, and there- 

 fore much more costly, than the globe itself. Then we 

 have the eight staircases of twenty-four flights each, and 

 the five or six miles of spiral platform, wide enough to 

 allow of a pathway next the surface of the globe and a 

 double line of road outside for the passage of some form 

 of auto-motor carriages. Then, again, the greater part of 

 this huge spiral platform is to be in movable sections, 

 which can be either swung aside or lifted up in order to 

 allow of an uninterrupted view of any desired portion of 



