beetles, shellac and sealing wax, oak galls, and cochi- 

 neal insects. 



49. Rubber. Shows five sources of true rubber, rubber 



substitutes, and products of both. 



50. Gums and Resins. Includes gum arabic, tragacanth, 



seaweed gelatine, catechu, turpentine, copal, gum dam- 

 mar, olibanum, myrrh, gamboge, tolu balsam, aloes, 

 and asafoetida. 



51. Carbon. Gives the story of peat, lignite, coal, coal tar, 



aniline dyes, petroleum and kerosene, lubricating oil, 

 paraffine, napthaline, creosote, charcoal, graphite, and 

 asphalt. 



52. Useful Non-metallic Minerals. Minerals used for pot- 



tery, glass materials, fertilizers, abrasives, etc. 



53. Ores and Metallic Minerals. Mining and uses of com- 



monest forms except iron. 



54. Iron. Tells the story of the mining and manufacture of 



iron in less detail than exhibit No. 23. 



55. Building Stones. Gives examples of the marbles, gran- 



ites, and sandstones most used in the United States, 

 together with clay and cement products, quicklime, 

 slate for roofing, etc. 

 56-57. Foreign and Native Woods. In preparation. 



58. Butterflies. Common local species. 



59. Moths. Life-history of Cecropia and lo moths. 



60. Rock Types. Classified according to Tarr's New Physical 



Geography, for use with high school classes. 



61-62. Blueprints of leaves of live oak, water oak, turkey oak, 

 and elm. For circulation to private schools only. 



63. Babylonian Clay Tablets. Five examples of cunei- 

 form writing. 



Stereoscopic slides illustrating any of the following subjects 

 will be lent with stereoscopes: Grand Canon of Arizona, Yo- 

 semite Valley, Yellowstone Park, Niagara Falls, Norway, Switz- 

 erland, glaciers, mountains, rock formations, volcanoes, caves, 

 and miscellaneous scenes from various countries. 



When first introduced the traveling exhibits were circulated 

 among only the six public graded schools of the city, the schools 

 themselves sending for the exhibits. Private teachers borrowed 

 occasionally. As the work grew it became necessary for the 

 Museum to assume responsibility for transportation. This 



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