INDEX. 



Pagp 



Altken, experiments with groimd feldspar 15-16 



Cobey, W. AV., letter relative to field experiments 25 



Dewey, J. S., letter relative to field experiments 24-25 



Feilitzen. von, experiments with ground feldspar 20-21 



Feldspar, composition ^ 



experiment to determine yield of potash to plants 26 



ground, no harmful effects from 30 



' potash in, cost per pound (table) 29 



production and value, 1901-1005 (table) 29 



substitute for potash salts, general conclusion 31 



Field experiments in Connecticut and Florida 24-25 



Fineness of grinding, effect 26-28 



Granite, potash content ^ 



Greenhouse experiments i-, — ^^ 



yield (table) 24 



Grinding, effect of fine -' 26-28 



Halladay, Edmund, letter relative to field experiments. 



25 



Headden, experiments with ground feldspar 18-19 



Hensel, experiments with ground feldspar 1.3-15 



Magnus, experiments with ground feldspar 13 



Maine State Experiment Station, experiments with ground feldspar 16-17 



Nilson, experiments with ground feldspar 17-18 



Olds & Whipple, letter relative to field experiments 25 



Phosphoric acid, content in vegetable ash (table) 8 



Potash as fertilizer, discussion ^ 8 



availability increased by grinding feldspar 27-28 



available, defined 21-22 



content in vegetable ash (table) 8 



defined 



importation of (table) 8 



in ground rock, availability 11-12 



method of extraction from ground rock 30-31 



total, defined 21-^2 



Potassium carbonate, cost 



Prianischnikow, experiments with ground feldspar 19-20 



Rock-forming minerals, relative abundance in rocks (table) 9 



Sestini, experiments with ground feldspar 18 



Soda, content in vegetable ash (table) 8 



Stone meal, use as fertilizer ^ 13 



Surface area of rock, increase by grinding 27-28 



Tobacco experiments by author with ground feldspar 12,22-24 



104 



32 



o 



