68 



PROCEEDINGS OF THE AMHERST MEETING 



MODELS ALREADY CONSTRUCTED 



Some excellent geological models have been constructed, of which the 

 following should be mentioned : 



1. G. H. Hudson, of Plattsburg, New York, has made a model of the 

 complex normal faulting of Yalcour Island, Xew York (figure 9). This 

 is an admirable model and brings out the complex structures which may 

 result from normal faulting, and also the danger, under such conditions, 

 of calculating the amount of section lost in any hiatus. If made some- 

 what larger and with the beds indicated by strongly contrasted colors, it 

 would be a useful addition to our geological equipment. 



2. Xo models better than the so-called Sopwith models, devised about 

 1841, to demonstrate the effects of normal faulting on coal beds and 

 copper and tin veins, have yet been made, and these should be universally 



Figure 9. — Model of a Part of Yalcour Island, Lake Ghamplain, New York 



used. The models of faults and folds, sold by Krantz, are more easily 

 seen on the lecture table than these, but are otherwise greatly inferior. 



3. A number of painted boxes which both illustrate different kinds of 

 folds and different kinds of faults have been made at the University of 

 Chicago, but experience has shown that only one, which shows a pitching 

 fold, is especially useful. 



4. There are a number of geological relief maps in the Field Museum 

 of Chicago, which, if slightly modified, of suitable size and with strongly 

 contrasting colors, would, with little doubt, be a welcome addition to the 

 teaching equipment in elementary geology and could also be used in ad- 

 vance courses. 



a. One model of a small gold mine (figure 10) was made and primarily 

 intended to illustrate methods of mining, but some features of vein struc- 

 ture are also reproduced. The model is about 4 feet long, 3 feet high, 

 and 10 inches thick, the dimensions being governed by the space available 

 for its exhibition. The scale is 10 inches to the foot. It represents a 



