Apeil 17, 1896.] 



SCIENCE. 



589 



THE FIRST PEINCIPLES OF AGRICULTURE. 



The above is the title of a neat book of 

 over two hundred pages by Edward B. Vor- 

 hees, Professor of Agriculture in Eutgers 

 College and Director of the Experiment 

 Stations of New Jersey. In a clear and at- 

 tractive manner the important first princi- 

 ples of the crop growers' craft are taken up 

 in logical order. There are fifteen chap- 

 ters, beginning with the plant constituents 

 and running through the formation of soils, 

 their composition and improvement, and 

 natural and artificial manures. To the lat- 

 ter fully a quarter of the book is devoted, 

 there being a chapter each upon nitrogen- 

 ous materials, phosphates, superphosphates 

 and potash, salts and methods of buying, 

 etc. Rotation of crops, selection of seed, 

 growth of animals, feeds and fodders, prin- 

 ciples of breeding and products of the dairy, 

 complete the list of general subjects treated. 

 To this is added composition and coefficient 

 tables as an appendix, closing with an in- 

 dex. 



The author has felt the need of a work 

 like this in his college teaching, and in con- 

 nection with his work among the farmers 

 themselves. Prof Voorhees believes that 

 agriculture can be taught in the country 

 schools and " it is here that such education 

 must begin if it is to reach and influence 

 the masses of farmers." With this convic- 

 tion and the endorsement of the New Jersey 

 Board of Agriculture and State Grange the 

 work has been prepared. It is, however, 

 a book for any farmer, for the contents deal 

 with those general principles that know 

 no State or country. Great stress has been 

 laid upon fertilizers, for Prof Voorhees, 

 from his especially large experience in this 

 branch of the work, sees that a clear under- 

 standing of manures, in the broad sense, 

 and their rational use, lie at the bottom of 

 all future successful agriculture in this 

 country. 



Byron D. Halsted. 



CUBBENT NOTES ON PHTSIOGBAPHY. 

 THE economic IMPORTANCE OF PENEPLAINS. 



The relation of geological deposits that 

 have economic value to physiographic con- 

 ditions, ancient and modern, has often been 

 illustrated. Coal beds record ancient low- 

 lands with extensive marshes of imperfect 

 drainage. In Pennsylvania the preserva- 

 tion of the coal now remaining is due to its 

 having lain all through Mesozoic time out 

 of reach of the weather, that is, beneath 

 baselevel ; for practically all the coal there 

 is below the level of the Cretaceous pene- 

 plain of that region. Again, the limonite 

 iron ores of the Appalachian valley are prod- 

 ucts of leaching on surfaces of low grade, 

 the floors of Tertiary valley lowlands, now 

 uplifted and more or less dissected. A re- 

 cent essay by Hayes (16th Ann. Eep., U. 

 S. G. S.) shows that the Georgia and Ala- 

 bama pocket deposits of bauxite, the oxide 

 of aluminum and an important source of 

 this metal, are limited to the Tertiary low- 

 land of the Coosa vallej^ ; thus again exem- 

 plifying the same general principle. The 

 source of the deposits is thought to be in 

 the underlying Cambrian shales; the faults 

 of the regions afford paths for upward trans- 

 portation ; and the low grade of the former 

 valley lowland promoted local accumulation 

 in pockets. Similar deposits may have 

 been formed on the more ancient Cretaceous 

 peneplain of the region ; but these have 

 vanished with the uplift and great dissec- 

 tion of that lowland. Similar deposits may 

 in future be formed when the narrow val- 

 ley trenches of to-day shall have widened 

 into broad floors. But at present the 

 bauxite pockets are practically limited to 

 the unconsumed portions of the Tertiary 

 valley lowland. Hence they stand at alti- 

 tudes of about 850 feet, although ranging 

 across the bevelled edges of several thou- 

 sand feet of strata. As a guide in search- 

 ing for new localities, this generalization is 

 of manifest value. 



