XX11 CONTENTS. 



The action of phosphatic guauos as manures . . .312 

 Proportion of fertilising constituents in guano . . 314 



Mode of application of guanos . . . . .315 



Quantity of guano to be used ...... 317 



Adulteration of guano . . . . . . .318 



So-called guanos 



Fish-guano 320 



Value of fish-guano 322 



Meat-meal guano ........ 324 



Value of meat-meal guano ...... 324 



Bat guano 325 



Pigeon and fowl dung 325 



APPENDIX TO CHAPTER VIII. 

 NOTE 



I. Peruvian guano imported into United Kingdom, 1865- 



1893 327 



II. Guano deposits of the world ...... 327 



III. Composition of concretionary nodules . . . .328 



IV. Table showing gradual deterioration of Peruvian guano, 



1867-1881 329 



V. Composition of different guanos ..... 329 



VI. Liebig's theory as to the action of oxalic acid in guano . 330 



VII. Analyses of dung of fowls, pigeons, ducks, and geese . 331 



CHAPTER IX. NITRATE OF SODA. 



Amount of exports . . . . . . . . .332 



Date of discovery of nitrate deposits ..... 333 



The origin of nitrate deposits . . . . . . .334 



Forbes and Darwin on the theory of their origin . . .335 

 Source of nitric acid in nitrate of soda ..... 337 



Guano theory of origin of nitrate of soda ..... 337 



Nitric acid in nitrate of soda probably derived from sea-weed . 339 

 Appearance of nitrate-fields .... ... 340 



The method of mining the nitrate of soda . . . .341 



Composition of caliche . . . . . . .342 



Extent of the nitrate deposits ....... 342 



Composition and properties of nitrate of soda . . . .343 



Nitrate applied as a top-dressing . . . . . .344 



Nitrate of soda encourages deep roots ..... 344 



