Absorption phenomena, 70
Abt, Dr. G., 51, 72
Acid “turning” of drench, 237
Acids, action of, 156
— fractionating, 270
— deliming with, 9
— in drench, 265
— to remove lime, cost of, 11
Adulteration in dog-dung, detecting, 144
Agglutinin, 144
Alum, a term for puer, 3
“Alumed” calf skins, 3
Amend’s bate, 193
Amido compounds, 156
Amines, 163, 206
— in dung, 154
Ammonia in puer liquors, 41
Ammonium phosphate, 45
Analyses, bird excreta, 53
— dog dung, 26, 150, 152
— drench, 249
— gas, 247
— grains, 7
— guano, 150
— hen dung, 150
— puer, 26
— ultimate, of dung, 153
Andreasch, F., 244
Anti-bodies, 143
Anti-calcium, 236
Arginase, 133
Artificial drench, 263
Ash of skin, 39
Authors, list of, 290

Bacillus butyricus, 112
— c, 172
— Coli commune, 94
— d, 106, 173, 174
— e, 107, 173
— erodiens, 97
— from pigeon dung bate, 172
Bacteria, action of, 160
— bate, examination of, 87
— bran, pure culture of, 269
— dung, 89, 98, 102, 161
— growth in various media, 105
— pigeon dung, 103
— putrefactive, 125
— “Sweating,” 105, 213
Bacterial diastase, 131
Bacterium furfuris, 241, 264, 269
— termo, 118
Barium salts from pure cultures of B. furfuris, 271
— — of volatile acids, 253
Bate, Amend’s, 193
— Becker’s patent, 227
— bird dung, 52
— Boehringer’s patent, 197
— concentration of salts in, 47
— Dermiforma, 189
— Eberle’s patent, 221
— Erodin, 179
— Esco, 192
— examination of bacteria in, 87
— glucose, 179
— Lederer’s, 196
— Nordlinger’s, 195
— Norris’s, 194
Bate, Nowak’s patent, 194
— Oake’s, 195
— Oropon, 140, 186, 219
— phosphates in, 43
— pigeon dung, 103
— Phosphorbutyralin, 195
— Popp and Becker’s patent, 197
— Puerine, 190
— Purgatol, 192
— reducing action of, 152
— Röhm’s patent, 219
— Simon’s, 195
— solid matter, influence of, 176
— soluble matter of, 176
— Sucanine, 191
— Tiffany’s, 179
— Wood’s American patent, 210
— — English patent, 205
— Zollikoffer’s, 178
Bayliss, Dr. W. M., 127
Béchamp, 280
Betulase, 132
Becker’s patent, 227
Bibliography, 282
Bile, 31
— action of, 159
— colouring matters, 30
— salts, effect on puer, 46
— — — — lipase, 142
Bird dung bate, 52
— excreta, composition of, 53
Boehringer’s patent, 194
Bone meal, 196
Books of reference, 89, 282
Bran bacteria, 240
— — pure cultures of, 269
— composition of, 257
— drench, 233
— — non-volatile bodies in, 254
— — products of fermentation, 247
— — sweet, 263
— — volatile bodies in, 249
— ferments, action on starch, 258
Brown, Adrian J. Prof., 274
Butyric acid, 11
— — fermentation, 111

Calcium in enzymes, 136
— phosphate, 45
Carlsberg vessel, 170, 214
Caroubinase, 132
Casease, 132
Castor-oil seed, 188, 232
Catalysts, 127
Cellulose fermentation, 110
Cerealin, 245, 260
Chemical composition of puer, 24
— deliming, 5
Chloroform, use of, in pancreatin solution, 151
Cholesterol, 30
Collagen, 56
Colloidal state, 57, 137
Concentration of salts in bate, 47
Condenser, Abbe’s, 87, 88
— dark ground, 87
Conductivity of puer liquors, 80, 81
Copenhagen conference, 180
Cultivation of bating bacteria, 199
Culture medium, 105, 207
Cytase, 132

Deliming, chemical, 5
Density of skin, 60
Dermiforma, 189
Dextrin, 259, 261
Diastase, 128, 131, 132
— Krawkov’s method of preparing, 135
Diastatic enzymes, 235
Digestive ferments, 148
— juices, 230
Dog dung, analyses of, 26, 150, 152
— bacteria in, 89, 98
— detecting adulteration of, 144
— fresh, bacteria in, 102
— influence of food on, 28, 95, 153
— method of analysis, 25
Dog dung, separating enzymes from, 134
— trypsin in, 134
Doerr and Reinhardt’s laboratory, 32
Drench, acid “turning” of, 237
— acids in, 156
— action of, 233, 242, 245
— artificial, 263
— bacteria in, 239
— damage, 236
— fermentations of, 238
— gases from, 242, 248
— glucoses in, 261
— “pinholey,” 238
— putrid “turning” of, 237
— sweet bran, 235
Dressing hides, 19
Drop culture, 87
Dung analyses, 26, 150, 152, 153
— mineral matter of, 153

Eberle, G., 13
Eberle’s patent, 221
Effront, Dr., 11
Eitner, 242, 244
Electrometric apparatus, 76
— method, 33, 49
Emulsin, 132
Enzymatic bates, 197
Enzymes, action of, 145
— — of serum on, 144
— — on skin, 140
— calcium in, 136
— defined, 127
— diastatic, 235
— from bacteria, 131
— hydrolysing, 132
— in dog’s dung, 137
— lipolytic, 145
— manganese in, 136
— preparation of, 134, 164
— proteolytic, 145
Erepsin, 133, 142
Erodin, 179
Erodin, stock liquor, 182
Esco, 192
Esters, synthesis of, 127
Ethyl butyrate, 165
Ethylamine butyrate, 42
— lactate, 42
— propionate, 42

Fahrion, Dr., 52
Falling, 67
— apparatus for measuring degree of, 82
Fat in puer, 25, 30
— in skins, 16
Feeding of dogs, 28, 95
Fermentation in the leather industry, 147
— nitrogen from, 279
Ferments, digestive, 148
— gall, 224
— hydrolysing, 132
— imino-lytic, 133
— oxidizing, 133
— oxylytic, 133
Flagellæ, staining of, 94
“Flaked” grain, 149
Formic Acid, 9
Fractionating acids, 250
Frankland and Frew, 249

Gall ferments, 224
Gamgee, 281
Gas analysis, 247
Gases from drench, 242, 248
— from pure cultures, 275
— intestinal, 281
Gayon, 280
Gelatin, 56
— density of, 63
— glucose, 267
— molecular weight of, 56
— peptonized, 168
Glucose bate, 179
— gelatin, 267
Glucoses in drench, 261
Glycerin, 141
Goat skins, 183
— — bating of, 231
Guano, analysis of, 150
Golding, J., 175
“Grains,” analysis of, 7

Harness backs, 17
Hauff, J., 236
Hen dung, analysis of, 150
Hexoses, 125
Hide-powder, density of, 66
Hides, bating of, 17
Houston, Dr., 93, 94, 97
Hydrogen from drench, 239
Hydrogen-ion concentration, 74, 79
Hydrochloric acid, use in deliming, 11
Hydrolysis, 128
— velocity of, 130
Hydrolysing enzymes, 132

Immendorf, 280
Imino-lactic ferments, 133
Indol, 95, 106
Infusoria, 123
Intestinal gases, 281
— juice, 225, 228
Inulase, 132

Jean, F., 41
Jones, Arnold Seymour, 75, 133

Kaolin, 176
Kathreiner, F., 46, 236
— bate trials by, 183, 184
Koch’s Jahresbericht, 125
Körner, Dr. Th., 67, 167
Kossel, Dr. A., 170
— and Dakin, 133
Kral, Prof., xv
Kühl, Dr. H., 236

Laccase, 133, 135
— manganese in, 135
Lactase, 132
Lactic acid, 10
— — from B. furfuris, 272
Lamb, M. C., 9
Law’s volumenometer, 61
Lecithin, 141
Lederer’s bate, 196
Lime in sheep grains, 23, 37
— in puer liquors, 36, 40, 44
— soaps, 16
Limed skin, 5, 7
Lion’s dung, 29
Lipase, 132, 141
— effect of bile salts on, 142
Lipolytic enzymes, 145
Liquor pancreaticus, 189

Malase, 133
Maltase, 132
Manganese in enzymes, 136
Mastering, a term for puer, 3
Mercaptans, 46
Measuring truck, 8
Meggitt, Loxley, 171
Metchnikoff, 93
Mineral matter of dung, 153
Minot, Prof., 81
Mixed cultures, 173
Molecular weight of gelatin, 56
Monads, 123
Morocco leather, 3
Moulds, 114, 126
Müller, 72
Muscle, contraction of, 73
Myrosin, 132
Myxomycetes, 116

Nencki, 107
Nitrogen from fermentation, 279
— in bran, 234
— in puer liquors, 48
Nitrites, use of, in bating, 193
Non-electrolytes, influence of, 72
Nördlinger’s bate, 194
Nowak’s patent, 194
Nuclein, 114

Oake’s bate, 195
Oenoxydase, 133
Olease, 133
Organic acids, use in deliming, 13
— — in puer, 155
Oropon, 140, 186, 219
Osmosis, 58
Osmotic pressure, 59, 167
O’Sullivan, J., 244
— and Thompson, 128
Oxalic acid fermentation, 111
“Oxidizing” skins, 193
Oxydin, 133
Oxylytic ferments, 133

Paddle, 14
Pancreas, 220
Pancreatin, action on skin, 138, 151
Papain, 132
Parker, Dr. Gordon, xv, 11
Pectase, 132
Pentoses, 125
Pepsin, 132
— action on skin, 138
Peptolytic ferments, 119
Peptonized gelatin, 168
Phosphates in the bate, 43
Phosphorbutyralin, 195
Pigeon dung, 103
“Pinholey” drench, 238
Plasmase, 132
Plate cultures, 103
Popp and Becker’s patent, 197
Precipitin, 144
Pribram, Dr., 73
Procter, Prof. H. R., 10, 55, 205, 210
Proteolytic enzymes, 145
— ferments, 119
Proteus bacteria, 118
Puer, amido compounds in, 156
— chemical composition of, 24
— fat in, 25, 30
— organic acids in, 155
— quantity used, 15
— reactions of, 31
— wheel, 13
Puerine, 190
Puering, solution of skin substance in, 47
Pure cultures of bran bacteria, 269
Purgatol, 192
Purin bases, 30
Putrefaction, 116
— See Nos. 58 to 78 of Bibliography, 282
— mechanism of, 107
— of meat, 120
Putrefactive bacteria, 107
Putrid “turning” of drench, 237

Reaction of puer, 31
Rennet, 128, 132
Rhamnase, 132
Rogers, Dr. Allen, 195
Röhm’s patent, 219
Ruge, 281

Sabatier and Senderens, 127
Salt solution, physiological, 87
Salts solution, 267
Sand, Dr., xv, 33, 81
Schorlemmer, K., 186
Scud, 51
Scudding, 16
— machine, 17
Serum, action of, on enzymes, 144
Shearling pelts, 183
Shrewsbury, H. S., 166, 281
Simon’s bate, 195
Skatol, 46
Skin substance, ash of, 39
Skin substance, density of, 60
— — fat in, 16
— — solution of, 47, 51
Soerensen, Prof., 43, 80
Solid matter in bate, 73
— — influence of, 175
Soluble matter of bate, 176
Soyka’s dilution method, 103
Spirillum volutans, 112
— delsulfuricans, 124
Spongy leather, 238
Staining and mounting, books on, 89
— of flagellæ, 94
Starch, action of bran ferments on, 259
Steapsin, 132
Stiasny, Prof. E., 282
Sucanine, 191
Sucrase, 128, 132
Sulphuric acid, use in deliming, 11
Sulphuretted hydrogen, 46
“Sweating” bacteria, 105, 213
Sweet bran drench, 235
Swelling, 67
— alkaline, 72
Symbiosis, 269
Synthesis of esters, 127
Syntonin, 32

Thio-acids, 196
Tiffany’s bate, 179
Toxins, 143
Trehalase, 132
Trent bridge laboratory, 107, 252
Trimethyl-amine, 107, 252
— butyrate, 42
Trypsin, 132, 133
Trypsin, in dog dung, 134
Turney, Sir John, scudding machine, 17
“Turning” of drench, 287
Tyrosinase, 133

Urea, 29
Urease, 132
Uric Acid, 29

Velocity of hydrolysis, 130
Volumenometer, 61
— air, 67
— Law’s, 61

Wladika, J., 256
Willcox, Dr. W. H., 243, 245
Wood’s American patent, 210
— English patent, 205
Wool bacteria, 174

Xylose, 125

Yeast water, 259
Yoghurt, 236

Zinc, effect on growth of moulds, 113
Zollikoffer’s bate, 178
Zoogloæ, 242
Zymase, 133

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