124 REPORT OF NATIONAL MUSEUM, 1919. 



The natural gas exhibit ah'eady referred to as the most important 

 accession of the year embodies a new principle in model construc- 

 tion. Heretofore the division's industrial models have been built 

 to a uniform scale, commonly a quarter inch to the foot. This leaves 

 it impossible to bring out the working of small features, however im- 

 portant, whereas large but relatively inconsequential features, such 

 as warehouses, loom up in altogether imdue prominence. With a 

 view to overcoming this objection, the natural gas model was con- 

 structed to a diminishing scale of perspective. Features deserving 

 of prominence or important as to detail, such as the operation of 

 well-drilling, stand in the foreground with the larger and less 

 consequential generalities relegated to the middle distance or back- 

 ground, which latter passes off imperceptibly into a painted landscape 

 carrying on back to the horizon. 



This newer type of model not only does away with the shortcom- 

 ings attendant on adherence to a uniform scale, but lends an appeal- 

 ing realistic effect. Its manifold advantages proved too great to be 

 ignored in respect to other exhibits already installed, and, after 

 meeting the emergency calls of wartime, the remaining energies 

 were directed to revising the soda, sulphur, and gold exhibits. In 

 particular, the large model designed with a view to depicting the 

 occurrence and mining of gold was practically rebuilt as to topog- 

 raphy and industrial layout. 



As it now stands this reconstructed gold model represents a beau- 

 tifully realistic expanse of mountain country cut by a river valley 

 and reaching back as far as the eye can see. All manner of gold 

 mining project is disclosed, from the lone miner with his pan in a 

 mountain brook to a battery of giant rams demolishing the land- 

 scape and a great dredge combing the river bottom; from the 

 "pardners" prospecting a little claim nestled away on a mountain 

 side to a great fully equipped lode-mining project. Here, in short, 

 the whole story of gold mining, a month's trip, an accumulation of 

 information beyond the range of more than the merest few specialist 

 engineers, awaits the visitor with a minute or two to spare in passing. 



The lead exhibit, too, has been notably advanced as to interest and 

 instructiveness in the Course of the year by the addition of a wall 

 chart and systematically grouped specimens, showing the develop- 

 ment of lead products and their uses. Otherwise the industrial ex- 

 hibits in mineral technology stand much as they were when reported 

 on a year ago with only incidental changes here and there. No field 

 work has been carried on; there has been little or no soliciting of 

 materials, and no distributions or exchanges negotiated. In all par- 

 ticulars, so far as practicable, matters of more restrictively museum 

 import were put aside. 



