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Hugi's Fundamental Experiment. A piece of fresh blue 

 glacier-ice, exposed to the rays of a powerful sun, in a very 

 short time crumbles together into a heap of individual ice- 

 grains 37 



Hugi's greatest achievement was his Winterreise ins 

 Eismeer, in January, 1832, a date which will be for ever 

 memorable in the history of the study of glaciers. Although 

 only a schoolmaster, it was carried out entirely at his own 

 expense. The organisation of it was complete, covering 

 observations in the valley with those which he and his party 

 were to make on the mountain. It lasted fourteen days, and 

 nearly every one of these days is the date of a fundamental 

 discovery in the natural history of land-ice .... 308 



Recapitulation and Conclusion 309 



No. 9. ON THE USE OF THE GLOBE IN THE STUDY OF 



CRYSTALLOGRAPHY. (From the Philosophical Magazine, 

 1895, S. 5, Vol. XL, pp. 153-172.) 313 



In this paper the usefulness of the Globe in the study of 

 solid Geometry generally is explained. The term crystallo- 

 graphy used in the Title refers to a particular case where 

 polyhedra are limited by certain symmetries. 



The blank globe, whether black or white, with the divided 

 circles belonging to it, is a calculating machine, adapted to 

 the solution of all the problems to which the analytical 

 methods of spherical trigonometry are usually applied . .313 



The globes which I used were those of 22 centimetres 

 diameter, which the firm of E. Bertaux of Paris supply. For 

 measuring purposes a system of divided circles of the same 

 radius as the sphere, called the Metrosphere, is supplied. 

 The real usefulness of the globe is not to be learned by theory 

 or precept, but by actual experience in the solution of problems 

 whether the study be astronomy or navigation or geography 

 or crystallography 2 14 



A detailed example is given of the use of the globe as 

 applied to a polyhedron of any number of plane faces, 

 arranged in any way so as to completely enclose the space . 315 



When the operation described has been performed, we 

 have on the globe a number of points which form a complete 

 catalogue of the faces of the polyhedron or crystal. Similarly 

 the arcs connecting each pair of poles furnish a catalogue of 

 the inclination of every single face to every other . . . 316 



By another graphic process we obtain a catalogue of all 

 the plane angles occurring on the faces of the polyhedron . 317 



