wm^*m 



Ward's Natural Science Establishment 



A Supply-House for Scientific Material. 



Founded 1862. Incorporated 1890. 



A few of our recent circulars in the various 

 departments : 



Geology: J-3. Genetic Collection of Rocks and Rock- 

 forming Minerals. J-188. Price List of Rocks. 



Mineralogy: J-109 Blowpipe Collections. J-74. Meteor- 

 ites, ' J-190. Collections. . J-197. Fine Specimens. 



Paleontology: JV185. Complete Trilobites. J-115. Collec- 

 tions. J-140. Restorations of Extinct Arthropods. 



Entomology: J-33. Supplies. J-125. Life Histories. 

 J-198. Live Pupae. 



Zoology: J-116. Material for Dissection. J-26. Compara- 

 tive Osteology/ J-94. Casts of Reptiles, etc. 



Microscope Slides: J-189. Slides of Parasites. Cat. 32 

 and 35. Rocks. 



Taxidermy: J -22. Bird Skins. J-31. Mammal Skins. 



Human Anatomy: J-16. Skeletons and Models. 



General: J-193. List of Catalogues and Circulars. 



Ward's Natural Science Establishment 



84-102 College Ave., Rochester, N. Y., IT. S. A. 



READY SHORTLY 



THE PHYSICS OF THE AIR 



by 



William J. Humphreys, Ph.D., 



Professor of Meteorological Physics 

 United States Weather Bureau 



A rational and deductive treatise on the physics 

 of the atmosphere. 



Of great value to meteorologists, physicists and the aviator 



650 pages, many illustrations, 8vo. 

 Price $5.00. 



Address orders and inquiries to 



THE FRANKLIN INSTITUTE 



PHILADELPHIA, U. S. A. 



