56 



32. Interference Apparatus, consisting of a tuning fork 

 with three resonators of which two are opposite the faces 

 of the prongs and the third is opposite the space between 

 them. 



Nos. 31 and 32 are exhibited by the Department of 

 Applied Mathematics, the College of the City of New 

 York, by A. G. Compton. 



PHYSIOGRAPHY. 



In Charge of R. E. Dodge. 



1 . Topographic Map of Crater Lake, Oregon ; together 



with description illustrative of the same. A new map 

 lately issued by the United States Geological Survey. 



2. Physical Map of Europe in the Habenicht-Sydow series. 



Exhibited by the American agent. The J. L. Hammett 

 Co., 352 Washington Street, Boston, Mass. 



3. Topographic Model of Southern New England. 



Scale, one inch equals two miles; vertical exaggeration 

 3. Tilted, dissected and partially drowned peneplain, 

 with monadnocks rising above it, and lowlands sunk into 

 it along the softer rocks. Exhibited by maker, E. E. 

 Howell, 612 17th Street, N. W., Washington, D. C. 



4. Topographical Model of New York and Vicinity ; 



exhibited by the maker, Mr. Howell. This model is 

 upon the same scale as the one of Southern New En- 

 gland. Also same model slated. 



5. Relief Map of New Jersey; vertical exaggeration 10. 



Recently issued and exhibited by the State Geological 

 Survey of New Jersey. 



6. Model of Coastal Plain, showing the typical physio- 



graphical features of such a region. Exhibited by the 



