Chapter XXVI: The Rothamsted Experiments (2)

Kainit, as a fixer, 247;
potash in, percentage of, 214, 220, 421;
rate of application of, 423.

Kaolin clay, analysis of, 104.

Karmrodt, analysis of Chincha Island guano, 305;
of concretionary nodules, 328.

Karnallite, potash in, 220.

Kellner, experiments on nitrification by, 52.

Kelp, potash in, 420.

Kieserite, 420.

Kinnaird, Lord, experiments by, with farmyard manure, 289.

Kitchen-garden soil, nitrogenous matter in, 122.

Knop on condition of nitrates in soil, 138.

Koosaw River, phosphates from, 376.

Kreatin assimilated by plants, 47.

Kuria Muria guano, 309, 328.

Labrador, guano deposits at, 328.

Labradorite, 214;
potash in, 220.

Lacepede Island guano, 309, 328;
phosphoric acid in, 330.

Lahn phosphate, 379.

Lava, phosphoric acid in, 202, 211.

Lawes, Sir J. B., and Gilbert, early researches of, at Rothamsted, 34;
experiments with farmyard manure, 271;
experiments with Peruvian guano, 301;
inauguration of Rothamsted experiments by, 33;
on composition of farmyard manure, 291;
on manuring of wheat, 483;
on motion of plant's sap, 56;
on percentage of food in excreta, 233;
on rate of nitrification, 186;
on sources of plant-nitrogen, 43;
on sulphate of ammonia, 356;
on unexhausted manures, 550, 557-559.

Lawes, Sir J. B., experiments with guano by, 301;
manufacture of superphosphate by, 382;
on application of superphosphate, 395;
on bones, 359;
on composition of farmyard manure, 291;
on farmyard manure, 477;
on loss of nitrates, 142;
on sources of nitrogen, 154.

Leather, as manure, 428;
nitrogen in, 428.

Leaves, dried, as litter, 242;
nitrogen in, 242;
phosphoric acid in, 242;
potash in, 242.

Legrange, Charles, on extent of nitrate-fields, 343.

Leguminous plants, benefited by basic slag, 414
--by potash, 523;
fixation of free nitrogen by, 42;
gain of nitrogen with, 135;
manuring of, 522-527, 530;
nitrogenous manures hurtful to, 523.

Lehmann on ammonia as plant-food, 50, 352.

Leipzig, bones from, 361.

Leones, guano deposits at, 327.

Leucite, potash in, 220.

Lias chalk, phosphoric acid in, 211.

Liebig, criticism of humus theory by, 25;
dissolved bones discovered by, 361;
first report to British Association, 24;
manufacture of superphosphate from bones by, 359;
mineral theory of, 26-29;
on ammonia as a manure, 352;
on importation of bones by Britain, 360;
researches of, in agricultural chemistry, 23-32;
services of, to agricultural chemistry, 31;
theory of manures by, 29;
theory of, on rotation of crops, 29.

Light, action of, on plant-growth, 38.

Lime, 449-461;
abundant occurrence of, 452;
action of, 461
--contradictory, 450
--not thoroughly understood, 449
--on nitrogenous organic matter, 460
--on soil's texture, 455;
antiquity of, as a manure, 449;
binding effect of, 457;
biological action of, 459;
caustic, 453;
chemical action of, 457;
decomposes minerals, 458;
different forms of, 453;
effect of, on soils, 112;
fixed by soils, 58;
in ash of plants, 54;
mechanical functions of, 455;
mild, 453;
necessary for nitrification, 171, 459
--for plant-growth, 55, 450;
neutralises acidity in soils, 458;
phosphates of, 385-388;
pig excrements contain, 281;
prevents clay puddling, 456;
returned to soil, 452;
soils contain, 450-452.

Limestone, analyses of, 106;
evaporation of water from, 99;
occurrence of, 452.

Linseed, imports of, 153;
manurial constituents of, 282.

Linseed-cake, manurial constituents of, 282.

Liquid manure, 442-444.

Lithia in ash of plants, 55.

Litter, loam as, 239;
peat as, 240;
straw as, 236;
uses of, 236.

Lloyd on fattening animals, 253.

Loam, as litter, 239;
evaporation of water from, 99;
poor in fertilising matter, 239.

Lobos, guano deposits at, 327.

Lobos de Afuera guano, 302, 327.

Macabi Island guano, 302, 327;
nitrogen in, 329;
phosphoric acid in, 329.

Maercker, Professor, on destruction of nitrifying organisms, 177.

Magnesia, fixed by soils, 58;
in ash of plants, 54;
in pig excrements, 281;
necessary for nitrification, 171;
necessary for plant-growth, 55;
sulphate of, as a fixer, 246, 285.

Maize, absorbs ammonia, 352;
fertilising ingredients removed from soil by, 485;
manurial constituents in, 282;
source of nitrogen, 153.

Malden Island guano, 309, 328;
phosphoric acid in, 330.

Malpighi on importance of atmospheric air for germination, 39.

Malt-dust, manurial constituents in, 282.

Manganese, oxide of, in ash of plants, 54.

Mangels, fertilising ingredients removed from soil by, 485;
guano a manure for, 318;
manurial constituents in, 282;
manuring of, 346, 511, 513, 514;
Rothamsted experiments on growth of, 568.

Manitoba soils, nitrogen in, at various depths, 156;
rate of nitrification in, 186.

Manure, cow, 247;
farmyard, 223-292;
horse, 243;
liquid, 442-444;
meaning of word, 109;
pig, 250;
sewage, 430-441;
sheep, 251;
stable, from peat-moss, 283
--wheat-straw, 283.

Manures, action of, 61;
analysis of, interpretation of, 539-544;
application of, 474-492;
method of, 531-538; cash prices of, 555;
equal distribution of, 531;
functions of, 109, increase soil-fertility, 474;
intrinsic value of, 545;
lasting effects of, 483;
methods of valuing, 544;
minor artificial, 424-429;
mixing of, 531-538;
nitrogenous, 293-359;
phosphatic, 359-417;
potassic, 418-423;
quantities of, applied to oats, 504;
unexhausted, 549-552, 558;
units for determining commercial value of, 554;
valuation of, 539-559;
value of, deduced from experiments, 548;
various classes of, 111-114.

Manurial constituents of various foods, 282.

Manurial ingredients, unit value of, 544.

Manuring of, barley, 495-498;
beans, 525-527, 530;
cabbages, 528;
cereals, 493-504;
clover, 524;
common farm crops, 493-530;
grass, 504-510;
hops, 528;
leguminous crops, 522-528;
mangels, 511, 513, 514;
oats, 493-504;
peas, 527;
potatoes, 517-522;
roots, 510-517;
turnips, 510, 511, 513-517;
wheat, 499-501.

Maracaibo guano, nitrogen in, 330;
phosphoric acid in, 330.

Marl, phosphoric acid in, 211.

Marsh-gas from farmyard manure, 258.

Meadow-hay, fertilising ingredients removed from soil by, 485;
manurial constituents in, 282;
Rothamsted experiments on manuring of, 570.

Meadow-land, benefited by basic slag, 414, 508;
manuring of, 508;
Norfolk experiments on, 509.

Meat-meal guano, 320, 324;
composition of, 152;
imports of, 324;
manufacture of, 324;
nitrogen in, 324;
phosphoric acid in, 324;
rate of nitrification in, 192;
source of nitrogen, 152;
value of, 324.

Mechi on liquid manure, 442.

Mejillones guano, 309, 327;
phosphoric acid in, 330.

Mene, on sources of plant-nitrogen, 42.

Menhaddo, guano manufactured from, 322.

Mexico phosphate, 308, 328.

Mica, analysis of, 105;
potash in, 214, 220.

Micro-organisms, convert ammonia into nitrous acid, 167;
convert nitrous acid into nitric acid, 168;
effect fermentation, 80;
effect fixation of free nitrogen, 44;
effect nitrification, 161;
oxidising power of, 197.

Mild lime, 453.

Milk, nitrification in albuminoids of, 182;
nitrogen removed in, 147;
phosphoric acid removed in, 207;
potash removed in, 218.

Mineral phosphates, 373-381;
value of, as a manure, 380.

Mineral salts necessary for nitrification, 52.

Minor artificial manures, 424-429.

Mixing manures, 532-538;
ammonia lost in, 533;
nitric acid lost in, 536;
phosphates reverted in, 536.

Moisture, atmospheric, action on guano, 300;
in farmyard manure, 260;
in manures, 543;
necessary for nitrification, 52, 176.

Molds, 94.

Mona guano, 309.

Mond, Ludwig, on nitrogen in coal, 354.

Monks guano, 327;
phosphoric acid in, 330.

Monocalcic phosphate, 386;
formula of, 398;
molecular composition of, 398;
percentage composition of, 398;
reversion of, with iron and alumina compounds, 399
--with tricalcic phosphate, 399.

Mulder on humus in soil, 47, 126.

Mueller, A., on nitrogen in soil, 121, 124.

Munro, Dr J. M. H., on nitrification, 52;
on sewage-sludge as manure, 439;
on urine voided, 292.

Muentz, on ammonia in air, 118;
on nitrifying organisms in soil, 180;
on oxidising power of micro-organisms, 197.

Muriate of potash, application of, 423;
forms calcium chloride, 422;
harmful effects of, 421;
more concentrated than sulphate, 422.

Mustard, 139.

Navassa phosphate, 308, 328, 379.

Nesbit on composition of guano, 301.

New Granada, guano deposits at, 327.

New Zealand, meat-meal guano from, 324.

Nile, nitrates in waters of, 159.

"Nitraries," 163.

Nitrate-fields, appearance of, 340;
origin of, 334.

Nitrate of soda, 332-351;
amount exported from Chili, 151, 332, 351;
amount imported into Britain, 151, 351;
appearance of fields of, 340;
application of, 347;
Chili and Peru chief source of, 161;
composition of, 343;
crops suited by, 346;
discovery of deposits of, 333;
extent of deposits of, 342;
encourages deep roots, 344;
formation of fields of, 334-340;
method of applying, 347;
method of mining, 341;
nitric acid in, source of, 337;
nitrogen in, percentage of, 343;
not an exhausting manure, 345;
origin of fields of, 334;
properties of, 343;
quantity to apply, 348;
shipments of, 351;
soils benefited by, 348;
source of
nitrogen, 150;
top-dressing with, 344.

Nitrates, amount lost by drainage, 140;
amount produced at different times, 189;
amount in soil, 129;
conditions diminishing loss of, 139;
constantly formed in soil, 138;
in barley-soils, 158;
in cropped soils, 130, 157;
in drainage-waters, 160, 188;
in fallow-soils, 129;
in manured wheat-soils, 131, 157;
in soil, 129, 162;
lost by drainage, 137;
most formed in summer, 139;
nitrogen as, in Rothamsted soils, 198;
position of, in soil, 188;
quantity formed in fallow-fields, 188.

Nitre, beds, 163;
occurrence of, 162;
soils of India, 162.

Nitric acid, amount of, supplied to soil by rain, 155;
derived from sea weed, 337;
formed from ammonia, 118;
formed from nitrous acid, 168;
in farmyard manure, 259;
in soil, 128;
lost in mixing manures, 536;
most important nitrogen compound for plants, 161;
relation of, to plants, 50;
source of, in nitrate of soda, 337.

Nitrification, 51, 52, 161-198;
action of gypsum on, 173;
alkalinity necessary for, 172;
in asparagin, 182;
bearing of, on agriculture, 193;
in bones, 182;
cause of, 165;
conditions favourable for, 170;
denitrification, 177-179;
effected by micro-organisms, 51, 167;
in ethylamine, 182;
in fallow-fields, 184;
food-constituents necessary for, 170;
field experiments on rate of, 187;
in gelatin, 182;
in horn, 182;
laboratory experiments on rate of, 185;
in manures, 190, 192;
in milk albuminoids, 182;
mineral salts necessary for, 52;
moisture necessary for, 52, 176;
old theories on, 196;
organic matter not necessary for, 169, 196;
oxygen necessary for, 52, 173;
plant-roots promote, 181;
in rape-cake, 182;
rate of, 183;
rotation of crops, bearing of, on, 195;
soil best suited for, 192;
in subsoils, conditions favourable for, 181;
substances capable of, 181;
in summer, 183;
sunlight, effect of, on, 176;
temperature necessary for, 52, 175;
in thiocyanates, 182;
in urea, 182;
in wool, 182.

Nitrifying organisms, depth found at in soil, 180;
distribution of, in soil, 179;
effect of poisons on, 176;
organic matter not required by, 169.

_Nitrobaeter_, 167.

Nitrogen, 115-160;
absorbed by soil, 81, 131;
accumulates in pastures, 134;
in air, 116;
as ammonia in soils, 127;
amount of, in plants, 40;
amount of, in soil, 123;
artificial supply of, 150;
in bat guano, 325;
in bones, 363, 364;
combined, in air, 118;
combined, in rain, 119, 155;
condition of, in manures, 540;
converted into nitrates in soil, 51;
in cow-dung, 226-228;
in cow excrements, 278;
in cow-urine, 230;
difference between surface and subsoil, 126;
different forms of, 45, 116;
dissolved in rain, 131;
in dried blood, 424;
in farmyard manure, 260;
in fish-guano, 321;
fixation of free, 136;
forms of, in plants, 491;
free, relation of, to plant, 117;
gain of, with leguminous crops, 135;
in guanos, 329;
in hoofs and horns, 426;
in horse-dung, 226-228;
in horse-manure, 243;
in horse-urine, 230;
importance of, in soil, 88;
in lean flesh, 424;
in leather, 428;
least abundant of manurial ingredients in soil, 271;
loss of, artificial sources of, 144;
loss of, by crops, 144;
loss of, on farm, 146;
loss of, sources of, 137-150;
loss of, total amount of, 142;
lost in the arts, 148;
lost in free condition, 141;
lost in treating farmyard manure, 146;
lost in milk, 147;
lost by retrogression, 142;
in Manitoba soils, 156;
in meat-guano, 324;
nature of, in soil, 124;
as nitrates in soil, 128;
as nitrates in cropped soils, 130, 157;
as nitrates in Rothamsted soils, 198;
as nitrates in wheat-soils, 157;
in nitrate of soda, 343;
nitric, in soil, 128;
organic, absorbed by plants, 47;
organic, in soil, 125;
original source of, in soil, 133;
in oxen excrements, 280;
in pasture-lands, 158;
peat-soils richest in, 123;
in Peruvian guano, 302, 306, 307, 329;
in pig-dung, 226-227;
position of, in agriculture, 115-160;
relative manurial value of, 556;
Rothamsted experiments on, 115;
in scutch, 427;
in sewage, 431;
in sewage-sludge, 439;
in sheep-dung, 226-228;
in sheep excrements, 280;
in sheep-urine, 230;
in soil, 120;
in soil, portion of, easily nitrifiable, 187;
in soils at various depths, 156;
in soot, 428;
source of, in plants, 15, 16, 40-52;
sources of soil, 131-137;
in straw, 237, 243;
in subsoil, 121;
in surface-soil, 121;
in swine-urine, 230;
in woollen rags, 427.

Nitrogenous guano, 300-308, 329.

Nitrogenous manures, application of, 478;
benefit cereals, 494;
hurtful to leguminous crops, 523.

Nitrogenous organic substances, in Chincha guano, 305;
in concretionary nodules, 328.

_Nitrosomonas_, 167.

Nitrous acid, converted into nitric acid, 168;
formed from ammonia, 167.

Nobbe, on fixation of free nitrogen, 136;
on potash in soil, 108.

Noellner on origin of nitrate-fields, 339.

Norfolk, coprolites from, 374;
experiments on barley, 497
--on meadow-land, 509
--on turnips, 513.

North America, guano from, 298, 328.

Norwegian apatite, 375.

Oak-tree, water transpired by, 71.

Oat-straw, composition of, 238;
manurial constituents in, 282.

Oats, Arendt's experiments with, 503;
avenine in, 503;
fertilising ingredients removed from soil by, 485;
hardy crop, 502;
manurial constituents in, 282;
manuring of, 501-504;
nitrogen removed in crop of, 148;
require mixed nitrogenous manures, 502;
source of nitrogen, 153;
Rothamsted experiments on growth of, 567.

_Oficinas_, 342.

Ohlendorff, introduction of dissolved guano by, 311.

Oilcakes, imports of, 153;
source of nitrogen, 153.

Oil-seeds, source of nitrogen, 153.

Oligoclase felspars, 103, 214;
composition of, 103;
potash in, 220.

Organic matter, in bones, 363;
in dung, 228, 260;
in manures, 543;
not necessary for nitrifying organism, 169.

Orthoclase felspars, 103, 214;
composition of, 103;
potash in, 220.

Ox-dung, fertilising ingredients in, for food consumed, 228.

Ox-urine, fertilising ingredients in, 232.

Oxalic acid in guano, action of, 330.

Oxen, excrements of, 280;
food aided by, 280;
solid excreta voided by, 280;
urine voided by, 280.

Oxidation, 79;
products of, 79, 80.

Oxygen, absorbed by plant-roots, 81;
absorbed by soil, 81;
evolved by plants, 11;
necessary for fertility, 81;
necessary for nitrification, 52, 173;
percentage of, in plants, 39;
source of, in plants, 39.

Pabellon de Pica, guano from, 298, 302, 327;
nitrogen in, 330;
phosphoric acid in, 330.

Pacific Islands, guano from, 298.

Pacific Ocean, sea-weed in, 339.

Palagonite as potash manure, 213.

Palm-kernel meal, manurial constituents in, 282.

Pasteur, on fermentation in urine, 255;
on nitrification, 166.

Pastures, accumulation of nitrogen in, 134;
benefited by basic slag, 414;
deficient in lime, 451;
effect of manure on herbage of, 505;
nitrogen in, 158;
permanent, 138, 194
--manuring of, 509;
season influences, 507;
soil influences, 507.

Patagonian guano, 308, 327;
nitrogen in, 330;
phosphoric acid in, 330.

Patent phosphate meal, 405.

Patillos, guano deposits at, 327.

Patos Island, guano deposits at, 328;
phosphoric acid in, 330.

Patterson on superphosphate, 399.

Payen and Boussingault on composition of dried flesh, 425.

Peas, manurial constituents in, 282;
manuring of, 527;
phosphorus in, 205;
source of nitrogen, 153.

Peat, absorbing properties of, 239;
adulterant of guano, 317;
analysis of stable-manure from, 281;
litter, 239;
nitrogen in, 240;
retaining properties of, 240;
soils, 123.

Pelicans, guano from, 297.

Penguin Island guano, 330;
nitrogen in, 330;
phosphoric acid in, 330.

Penguins, guano from, 297.

Percival on carbonic acid in plants, 12.

Peru, guano deposits in, 327;
guano first used in, 297;
nitrate of soda from, 161, 162.

Peruvian guano, 300-306;
appearance of, 303;
composition of, 304-306;
deposits of, 301;
imports of, 151, 297;
source of nitrogen, 151.

Peters and Eichhorn on solvent power of salt, 471.

Petzholdt on sources of plant's nitrogen, 42.

Pfeffer on action of light on plant-growth, 38.

Phoenix Island guano, 309.

Phosphate of iron in Chincha guano, 305.

Phosphate of lime, in Algerian phosphate, 379;
in apatite, 374;
in Belgian phosphate, 377;
in bones, 364;
in Cambridge coprolites, 374;
in Carolina phosphates, 376;
in crust guanos, 379;
in Estremadura phosphate, 375;
in Florida phosphate, 378;
in French phosphates, 379;
in Lahn phosphates, 379;
in Somme phosphate, 378;
reverted in mixing manures, 537.

Phosphates of lime, 385-388, 398;
importance of mechanical condition of, 542.

Phosphates, mineral, 373-381;
imports of, 381;
value as a manure, 380.

Phosphatic guano, 308, 330.

Phosphatic manures, application of, 480.

Phosphoretted hydrogen in farmyard manure, 258.

Phosphoric acid, 199-211;
in ash of plants, 54;
in basic slag, 404;
in bat guano, 325;
in bones, 363;
condition of, in soil, 203;
in cow-dung, 226-228;
in cow excrements, 280;
in cow-urine, 230;
in farmyard manure, 260;
in fish-guano, 321;
fixed by soils, 58;
gain of, 208;
in guano, percentage of, 329, 330;
guano a source of, 202;
in hoofs and horns, 426;
in horse-dung, 226-228;
in horse-urine, 230;
importance of, 88;
loss of, artificial sources of, 206
--by drainage, 206
--in farmyard manure, 208
--in milk, 207
--in sewage, 208
--sources of, in agriculture, 205;
in meat-guano, 324;
mineral sources of, 200;
necessary for plant-growth, 55;
occurrence of, in animals, 205
--in nature, 199
--in plants, 204
--in soil, 203;
in oxen excrements, 280;
in pig-dung, 226, 227;
in pig excrements, 281;
in pig-urine, 230;
position of, in agriculture, 199-211;
relative trade values of, in manures, 400;
in rocks, 202, 211;
in sewage-sludge, 441;
in sheep-dung, 226-228;
in sheep excrements, 280;
in sheep-urine, 230;
statement of, in analyses of manures, 541.

Phosphorite, 201, 374.

Phosphorus, in albuminoids, 205;
in animals, 205;
in beans, 205;
in peas, 205;
in plants, 204;
in pig-iron, 401.

Physical properties of soils, 66-87.

Pichard on action of gypsum on nitrification, 173.

Pig-dung, composition of, 226;
in dry state, 227.

Pig excrements, 281;
composition of, 281.

Pig-manure, 250;
amount produced per day, 251;
mineral matter in, 251;
nitrogen in, 251;
poor in nitrogen, 251.

Pig-urine, composition of, 230
--in dry state, 231.

Pigeon-dung, 320, 325;
analysis of, 331.

Pigs, excrements of, 281;
food consumed by, 281.

Pisagua, nitrate-fields at, 340.

Plant, action of light on, 38;
amount of hydrogen in, 40
--nitrogen in, 40
--oxygen in, 40;
ash constituents of, 53-55;
carbon fixed by, 37, 38;
food, absorption of, by, 55;
phosphoric acid in, 204;
potash in, 216;
proximate composition of, 36;
relation of ammonia to, 48-50;
source of hydrogen in, 40
--nitrogen in, 40-52
--oxygen in, 39, 40.

Plant-food, absorption of, 490;
amount of soluble, in soil, 100;
early theories on source of, 4;
retained by soil, 57.

Plant-roots, grow downwards, 84;
nitrification promoted by, 181;
openness required by, 83;
room required by, 85;
soil in relation to, 84.

Pliny, on lime as a manure, 449;
on salt as a manure, 465.

Pockets a source of phosphoric acid, 202.

Poisons, effect of, on nitrifying organisms, 176.

Polstorff on ash constituents of plants, 53.

Polyhallite, potash in, 220, 420.

Porphyry, in guano, 303;
phosphoric acid in, 202, 211.

Potash, 212-220, 418-423;
in ash of plants, 54;
in barilla, 420;
chloride of, 218;
condition of, in soil, 216;
in cows' excrements, 280;
in drainage-waters, 217;
in farmyard manure, 260;
in felspars, 220;
in fleece, 217;
fixed by soils, 58;
importance of, in soil, 88;
in kelp, 420;
less important than phosphoric acid, 212;
manures, 218, 418-423;
muriate of, 218, 421;
necessary for nitrification, 171;
necessary for plant-growth, 55;
occurrence of, 213;
in ocean, 213;
in oxen excrements, 280;
in pig excrements, 280;
in plants, 216;
position of, in agriculture, 212-220;
relative manurial value of, 556;
Scottish soils supplied with, 419;
in sheep excrements, 280;
soda replaces, 466;
sources of loss of, 217;
in Stassfurt salts, 214;
statement of, in analyses of manures, 542;
in sugar-beet refuse, 219;
sulphate of, 218, 421;
in wood-ashes, 218, 220, 419.

Potash manures, 218, 418-423;
application of, 422, 480
--rate of, 423;
barilla as, 420;
crops suited for, 423;
relative importance of, 418;
soils suited for, 423;
sources of, 419;
Stassfurt salts as, 420;
wood-ashes a source of, 419.

Potassium phosphate in concretionary nodules, 328.

Potassium sulphate, in Chincha guano, 305;
in concretionary nodules, 328.

Potatoes, effect of farmyard manure on, 520;
fertilising ingredients removed from soil by, 485;
grown with covered manure, 289;
Highland Society's experiments on, 518;
manurial constituents in, 282;
manuring of, 517-522
--in Jersey, 529
--influences composition of, 521;
potash removed in, 217;
Rothamsted experiments on, 519, 571.

Precipitated ammonium phosphate in concretionary nodules, 328.

Precipitated phosphate, 330, 387.

Precipitation, treatment of sewage by, 436.

Priestley, discovery of evolution of oxygen by plants, 11;
on nitrogen in plants, 40.

Prussiate of potash, manufacture of, 353.

Pugh on sources of plant-nitrogen, 42.

Punta de Lobos guano, 302;
nitrogen in, 303;
phosphoric acid in, 303.

Punta de Patillos, guano deposits at, 327.

Pyroxene, potash in, 220.

Quartz, evaporation of water from, 99.

Queensland, meat-meal guano from, 324.

Quercitan, experiments of, with roses, 8.

Rape-cake, capable of nitrification, 182;
manurial constituents in, 282.

Rape-seeds, imports of, 153.

Raza Island guano, 328;
phosphoric acid, 330.

Rectified guano, 311.

Relative trade values of phosphoric acid, 400.

Resin in guano, 305.

Retentive power of soils for water, 70-73.

Retrogression, nitrogen lost by, 142.

Reverted phosphates, 389-391;
determination of amount of, 391;
formation of, 387;
value of, 391.

Rhine, nitrates in waters of, 158.

Rice-meal, an adulterant of guano, 319;
manurial constituents of, 282.

Rocks, phosphoric acid in, 202.

Roots, influence of manures on composition of, 512;
manuring of, 510-522;
Norfolk experiments on, 513;
potash removed in, 217.

Rotation of crops, bearing of, on nitrification, 195.

Rotations, phosphoric acid in, 290;
potash removed in, 290.

Rothamsted, alternate wheat and bean rotation at, 524;
ammonia in rain at, 49;
barley experiments at, 566;
Broadbalk Field, alteration in composition of, 159
--manuring of, 159
--produce of wheat on, 159;
early experiments at, 33-36;
experiments, 560-572;
experiments with nitrate of soda at, 347;
experiments on nitrogen question at, 115
--mangel-wurzel, 568
--oats, 567
--potatoes at, 519
--value of nitrogen in farmyard manure, 271;
increase of nitrogen with manures at, 137, 513;
nitrates in barley-soils of, 158;
nitrates in cropped soils of, 130, 157;
nitrates in drainage of, 189;
nitrates in wheat-soils of, 131, 157;
nitrogen as nitrates in soils of, 129, 198;
nitrogen, decrease of, in soils, 159;
nitrogen in pasture at, 126;
pasture, increase of nitrogen in, 158;
retrogression of nitrogen at, 142;
soil, nature of, 561
--nitrogen in, at various depths, 156;
total amount of nitrogen lost at, 142;
turnip experiments at, 568;
unmanured fallow-land loses nitrogen by drainage at, 141;
wheat experiments at, 500, 562-565.

Roy on sources of plant-nitrogen, 42.

Rubidia in ash of plants, 55.

Ruffle, John, on superphosphate, 388.

Rye, manurial constituents in, 282.

Rye-grass suited for sewage, 435.

Rye-straw, summer, composition of, 238;
winter, composition-of, 238.

St Helena, experiments at, with Peruvian guano, 301.

Saldanha Bay guano, 328;
nitrogen in, 329;
phosphoric acid in, 329.

_Salinas_, 335.

Salm-Horstmar, Prince, on water-culture, 54.

Salt, 465-473;
action of, on crops, 472;
adulterant of guano, 319;
amount applied, 473;
antiquity of use of, 465;
an antiseptic, 468;
application of, 472;
clarifies water, 470;
coagulates clay, 470;
decomposes minerals, 470;
a germicide, 468;
indirect action of, 468;
mechanical action of, 470;
nature of action of, 465;
not a necessary plant-food, 466;
occurrence of, 467;
prevents rapid fermentation, 471;
quantity to apply, 473;
solvent action of, 470;
sources of, 468.

Saltpetre, formation of, 164;
occurrence of, 215;
plantations, 163.

Sand, absorptive power of, 68;
an adulterant of guano, 319;
calcareous, absorptive power of, 98;
siliceous, absorptive power of, 98.

Sandy soils deficient in lime, 451.

Sandwich Islands, guano deposits at, 328.

Saragossa Sea, sea-weed in, 339.

Saussure, De, on absorption of gases by soil, 81;
on nitrogen in plants, 41;
researches on plant-food by, 15.

Sawdust an adulterant of guano, 319.

Scheibler, Professor, on basic slag, 404.

Schloesing and Muentz, on nitrification, 51, 166;
experiments on rate of nitrification by, 185;
on denitrification, 179;
on ferments effecting nitrification, 167;
on fixation of free nitrogen, 42;
on ammonia in air, 119, 132;
on nitrogen absorbed by soil from air, 132;
on temperature favourable for nitrification, 175.

Schoenite, potash in, 220.

Schuebler, on absorptive power of soils, 98;
on retentive power of soils, 98.

Schulze on fixers, 246.

Scutch, 427;
manufacture of, 427;
nitrogen in, 427.

Sea-weed, nitric acid in, 339.

Seals, guano from, 297.

Seed, fertilising ingredients lodge in, 491.

Seine, nitrates in waters of, 158.

Senebier, Jean, on carbon in plants, 12;
on nitrogen in plants, 41.

Sewage, 430-441;
charcoal a filter for, 437;
crops suited for, 434;
denitrification in, 179;
dry matter in, 431;
effects of continued applications of, 433;
filters for, 437;
irrigation with, 431-433;
nitrification in, 166;
nitrogen lost in, 149;
phosphoric acid lost in, 149;
purified by soils, 435;
treatment of, by precipitation, 436;
value of, as a manure, 430.

Sewage-sick land, 433.

Sewage-sludge, 438-441;
as a manure, experiments with, 438;
nitrogen in, 439;
phosphoric acid in, 439;
profitable treatment of, 441;
value of, 439;
water in, 438.

Shale-works, sulphate of ammonia, from, 358.

Shark's Bay guano, 309, 328.

Sheep, excrements of, 280, 281;
solid excreta voided by, 280;
urine voided by, 280.

Sheep-dung, alkalies in, 226;
composition of, in dry state, 227;
most valuable excrement, 227;
nitrogen in, 226;
phosphoric acid in, 226;
water in, 226.

Sheep-manure, 251;
amount produced per day, 251
--per year, 252;
dry matter in, 252;
mineral matter in, 252;
nitrogen in, 252.

Sheep-urine, alkalies in, 230;
composition of, in dry state, 231;
most valuable urine, 231;
nitrogen in, 230;
phosphoric acid in, 230;
water in, 230.

Shoddy, 427;
production of, 152, 425;
nitrogen in, 152, 427.

Sicily, bones from, 360.

Sidney Island guano, phosphoric acid in, 330.

Siemens, Dr, experiments by, with light on plants, 38.

Silica, in ash of plants, 55;
in Chincha guano, 305;
jelly, 169;
necessary for plant-growth, 55.

Silicates, 102;
absorbed by cereals, 494.

Silicic acid fixed by soils, 58.

Simon on humus in soil, 47.

Slaked lime, 454.

Slugs killed by lime, 461.

Smut prevented by lime, 461.

Soda, in ash of plants, 54;
fixed by soils, 58;
necessary for plant-growth, 55;
nitrate of, 332-351;
in _salinas_, 335;
replaces potash, 466.

Sodium chloride in Chincha Island guano, 305.

Sodium phosphate in concretionary nodules, 328.

Sodium sulphate in concretionary nodules, 328.

Soil, 65-108;
absorptive power of, for water, 67, 98;
acids fixed by, 58-60;
action of lime on, 453;
ammonia absorbed by, 81;
amount of soluble plant-food in, 100;
artificial, 54;
barley, nitrates in, 158;
bases fixed by, 58-60;
best suited for nitrification, 192;
biological properties of, 92-96;
capacity for heat, 76-78;
carbonic acid absorbed by, 81;
chemical composition of, 87-92, 101-107;
colour of, 80;
cropped, nitrates in, 157;
denitrification in, 177;
evaporation from, 71, 72;
farmyard manure, action of, on, 272;
fertilising ingredients in, 87;
fertility of, 65-108;
fineness of, 69-70;
gases in, 100;
hygroscopic power of, 75-76, 99;
improved by humus, 272;
influence of farmyard manure on, 475;
on nitrification, 180;
manures increase fertility of, 474;
nitrates in, amount of, 128-131;
nitrifying organisms in, 179;
distribution of, 179;
nitrogen absorbed by, 81, 82, 131;
nitrogen accumulates, 133;
nitrogen in, amount of, 120-128;
nitrogen least abundant of manurial ingredients in, 270;
nitrogen at various depths in, 156;
oxygen absorbed by, 81;
phosphoric acid in, 203
--condition of, in, 203
--occurrence of, in, 203;
peat, 123;
possesses power of fixing ammonia, 57;
potash in, 215
--condition of, in, 216;
potential fertility of, 549;
power of, for absorbing gases, 81;
relation of, to plant-roots, 84;
retention of plant-food by, 57;
retentive power of, for water, 70-73;
sewage purified by, 435;
shrinkage of, 74;
variation in absorbing powers of, 82;
varieties of, 67;
virgin, 133;
water in, most favourable amount of, 75;
water-logged, 179;
wheat, nitrates in, 157.

Soluble phosphate, 386.

Sombrero phosphate, 308, 328, 330, 379;
phosphoric acid in, 330.

Somme phosphate, 378.

Soot, 428;
application of, rate of, 429;
crops suited by, 429;
nitrogen in, 428.

South America, guano deposits in, 327;
meat-meal guano from, 324.

Starbuck Island guano, 309, 328;
phosphoric acid in, 330.

Stassfurt salts, 214;
potash in, 215, 420.

Stead and Ribsdale on formation of basic slag, 407.

Stoeckhardt, on composition of solid excreta, 226;
on composition of urine, 229.

Storer, Professor, on composition of birds' dung, 331;
on composition of leaves, 242;
on fish-guano, 323;
on nitrogen removed in milk, 147.

Straw, composition of, 238;
imports of, 153;
as litter, 236, 248;
mineral matter in, 238, 243;
nitrogen in, 237, 243;
variation in composition of, 237.

Subsoil, conditions favourable for nitrification in, 181.

Suffolk coprolites, 374.

Sugar-beet refuse, potash in, 219.

Sulphate of alumina, a precipitant of sewage, 437.

Sulphate of ammonia, 352-358;
ammonia in, 355;
application of, 356;
composition of, 355;
a concentrated nitrogenous manure, 356;
converted into nitrates, 356;
from gas-works, 353;
from iron-works, 355;
from shale-works, 354;
manure for cereals, 356;
most easily nitrifiable manure, 191;
production of, 151, 358;
properties of, 355;
source of nitrogen, 149;
sources of, 353, 354, 358;
sulphocyanate of ammonia in, 355.

Sulphate of lime a fixer, 246.

Sulphate of magnesia, an adulterant of guano, 319;
as a fixer, 246.

Sulphate of potash, application of, 422
--rate of, 423;
compared with muriate, 421;
sources of, 218, 420.

Sulphuretted hydrogen from farmyard manure, 258.

Sulphuric acid, action of, on bones, 382
--on guano, 311
--on tricalcic phosphate, 398;
in ash of plants, 54;
as a fixer, 245, 285;
necessary for plant-growth, 55;
superphosphate manufactured with, 384, 388.

Superphosphate, 382-400;
action of, 392-395
--sometimes unfavourable, 395;
application of, 395
--rate of, 397;
composition of, 391;
discovery of, 382;
hastens early growth, 394;
high-class, 392;
low-class, 392;
manufacture of, 383-385
--phosphates suitable for, 384;
medium-class, 391;
production of, 382;
reversion in, 389, 399, 400
--causes of, 389, 390;
reverted in soil, 392.

Surprise Island guano, 328.

Swan Island guano, 328.

Swedes, fertilising ingredients removed from soil by, 485;
manurial constituents in, 282;
manuring of, 514.

Swine-dung, alkalies in, 226;
composition of, 227;
nitrogen in, 226;
phosphoric acid in, 226;
water in, 226.

Swine-urine, alkalies in, 230;
composition of, 231;
nitrogen in, 230;
phosphoric acid in, 230;
water in, 230.

Sydney Island guano, 309.

Syenite, 106;
phosphoric acid in, 202, 211.

Sylvin, potash in, 220.

_Symbiosis_, 44.

Tamarugal, Pampa de, nitrate deposit in, 340.

Tarapaca, nitrate deposits in, 340.

Temperature necessary for nitrification, 52, 175.

Tetracalcic phosphate, 387;
occurrence of, 387, 405;
solubility of, 387.

Thaer on application of farmyard manure, 275.

Thiocyanates, nitrification in, 182.

Thomas-Gilchrist process of steel-smelting, 402.

Thomas-slag. See Basic slag.

Tillage increases number of plants, 86.

Timor Island guano, 309.

Tobacco, potash in, 217.

Torrefied horn, 426.

Torrefied leather, 428.

Tortola guano, 309.

Trachyte, phosphoric acid in, 202, 211.

Transpiration, by elm-tree, 71;
by oak-tree, 71.

Trees, as pumping-engines, 76;
water transpired by, 71.

Tricalcic phosphate, 386, 398.

Tubercles on roots of plants, 44.

Tull, Jethro, theory of, on plant-growth, 9-11, 69, 109.

Turkey, dung produced by, 331.

Turnips, fertilising ingredients removed from soil by, 485;
manurial constituents in, 282;
manuring of, 510, 511, 513-517;
Rothamsted experiments on growth of, 568.

Twigs, potash in, 217.

Tyrosin, assimilated by plants, 47.

Ulmates in farmyard manure, 259.

Ulmic acid, in farmyard manure, 258;
in humus, 47.

Ulmin in humus, 47.

Uncovered farmyard manure, 263, 289.

Unexhausted manures, valuation of, 549-552, 558.

Unit value of manurial ingredients, 544.

Units for determining commercial value of manures, 554.

Urate of ammonium in Chincha Island guano, 305.

Urea, assimilated by plants, 46;
in farmyard manure, 257;
nitrification in, 182.

Uric acid, experiments with, 46;
in Chincha Island guano, 305.

Urine, 228;
amount voided, 291;
composition of, varies, 228;
contains digested manurial ingredients, 228, 232;
devoid of phosphoric acid, 205;
and dung, composition of, 234;
influence of food on, 229;
nitrification in, 197;
nitrogen in, 292;
potash in, 292;
voided by cows, 280;
voided by oxen, 280;
voided by pigs, 281;
voided by sheep, 280.

Uruguay, meat-meal guano from, 324.

Valuation of manures, 539-559.

Vegetation, desirable to have soil covered with, 194.

Venezuela, guano deposits at, 327.

Ville, Georges, on assimilation of ammonia, 50;
theory of, on source of plant-nitrogen, 41.

Vine, potash removed by, 216.

Virgin soils, 133.

Voelcker, Dr, analysis of apatite, 210
--of farmyard manure, 259;
on action of superphosphate, 395;
on fresh and rotted dung, 261, 286;
on guano, 316;
on salt as a manure, 473.

Voss, Hermann, on manures used, 152.

Wagner, Professor, on, application of basic slag, 416;
assimilation of organic nitrogen, 46;
experiments with basic slag, 408-413;
fineness of basic slag, 409;
manures, 412;
relative manurial value of nitrogen compounds, 556;
solubility of basic slag, 408.

Wallace, Dr, on sewage purification, 436.

Walruses, guano from, 297.

Warington, R,., on ammonia in rain, 49;
on appearance of nitrous organisms, 168;
on conditions favourable for nitrification, 181;
experiments on rate of nitrification, 186;
on composition of farmyard manure, 260;
on manufacture of superphosphate, 383;
on manurial constituents of foods, 282;
on nitrification in alkaline solutions, 197;
on nitrogen in excrements, 233;
on nitrogen in soil, 122;
on potash in wool, 227;
researches of, on nitrification, 35, 52, 166-168, 180, 186.

Water, absorbed by plants, 73;
amount of, transpired by plant-leaves, 56;
an adulterant of guano, 319;
a carrier of plant-food, 55;
in cow-dung, 226
--cow-urine, 230;
from decomposition of farmyard manure, 257;
in horse-dung, 226
--horse-urine, 230;
necessary for plant, 67;
in pig-dung, 226
--pig-urine, 230
--sheep-dung, 226
--sheep-urine, 230;
transpired by elm-tree, 71
--oak-tree, 71.

Water-culture, 54.

Water-logged soils, 179.

Waterloo, bones from, 360.

Way, Thomas, on retention of plant-food by soil, 57, 59;
on sewage, 437.

West Indies, guano from, 298.

Whales, guano from, 322.

Wheat, fertilising ingredients removed from soil by, 485;
Flitcham experiments on, 500;
manurial constituents in, 282;
manuring of, 499-501
nitrogen removed in crop of, 145;
requires nitrogenous manures, 499;
Rothamsted experiments on, 500, 562-565;
a source of nitrogen, 153.

Wheat soils, nitrates in, 157.

Wheat-straw, analysis of stable manure made from, 283;
composition of, 238;
manurial constituents in, 282.

White clover, growth of, promoted by lime, 451.

Wiegmann on ash constituents of plants, 53.

Wilfarth on nitrogen in plants, 44.

Wilting, 73.

Winogradsky, on nitrification, 52, 167, 169, 197;
on organisms in soil, 94.

Wolff on, analysis of manure-heap drainings, 290;
composition of fresh and rotten dung, 288;
assimilation of organic nitrogen by plants, 47;
relative manurial value of manurial compounds, 556;
urine, 232.

Wood-ashes as potash manure, 218, 419.

Woodhouse, researches of, on nitrogen in plants, 41.

Wool, capable of nitrification, 182;
potash in, 217.

Wool-waste, 427;
nitrogen in, 427.

Woolney, on organisms in soils, 93, 95;
on water in soils, 75.

Wrightson, Professor, on application of basic slag, 414.

Yeast, 94.

Yorkshire, bones first used in, 359.

Zeolites, potash in, 220

PRINTED BY WILLIAM BLACKWOOD AND SONS.

+---------------------------------------------------+ | Transcriber's Note: | | | | Carats (^) signify superscript figures. | | Underscores (_) followed by a number in curly | | brackets signify subscript figures. | | | | Typographical errors corrected in the text: | | | | Page 58 Eichorn changed to Eichhorn | | Page 134 diferent changed to different | | Page 464 superposphate changed to superphosphate | | Page 553 biophosphate changed to biphosphate | | Page 579 Gallopagos changed to Galapagos | +---------------------------------------------------+