V.—THE BACTERIOLOGY OF FERMENTED OR SOURED MILK 84
VI.—THE PREPARATION OF SOURED MILK IN THE HOUSE 125
VII.—THE PREPARATION OF SOURED MILK IN THE DAIRY 139
VIII.—SOURED MILK IN HEALTH AND DISEASE 151
THE OLDEST WOMAN IN THE WORLD AND HER SON _Frontispiece_
1.—MICRO-PHOTOGRAPH OF A DROP OF WHOLE MILK 58
4.—PHOTOGRAPH OF TWO PETRI DISHES, WHICH HAVE BEEN INOCULATED WITH ORDINARY MILK 60
6.—TESTING-GLASS FOR EXTRANEOUS MATTER IN MILK 62
9.—CONTINUOUS APPARATUS FOR THE PRODUCTION OF LARGE QUANTITIES OF SOURED MILK 82
12.—_Streptococcus lacticus_ (GROTENFELDT) GROWING ON LACTOSE-AGAR, STAINED BY GRAM'S METHOD 96
13.—PHOTO-MICROGRAPH OF PREPARATION FROM ARMENIAN SOURED MILK (MATZOON) 106
14.—GRANULE BACILLUS FROM YOGHOURT. SHREDDED PREPARATION OF A FRESH SKIM-MILK CULTURE 110
15.—GRANULE BACILLUS FROM YOGHOURT, CULTIVATED AFTER THE USUAL AGAR METHOD 110
16.—GRANULE BACILLUS FROM YOGHOURT. AGAR MILK SUGAR CULTURE 110
17.—_Bacteria W._ FROM MILK, CULTIVATED TWENTY-FOUR HOURS 110
18.—AGAR MILK SUGAR CULTURE. FROM THE ORIGINAL BULGARIAN YOGHOURT 112
19.—AGAR MILK SUGAR CULTURE. SURFACE COLONY OF GRANULE BACILLUS FROM CALF'S STOMACH 112
20.—AGAR MILK SUGAR CULTURE. DEEP-LYING COLONY OF GRANULE BACILLUS FROM CALF'S STOMACH 112
21.—AGAR MILK SUGAR. COLONY OF _Bacterium W._ FROM YOGHOURT 112
22.—TWO COLONIES OF _Bacillus Acidophilus_ FROM CALVES' MANURE 114
24.—SHREDDED PREPARATION OF BULGARIAN ORIGINAL YOGHOURT 114
25.—GRANULE BACILLUS FROM YOGHOURT. CULTIVATED IN SKIM MILK IN TWENTY-FOUR HOURS 114
26.—_Bacteria W._, AGAR MILK SUGAR CULTURE 116
27.—_Bacteria acidophilus_ FROM CALVES' MANURE 116
28.—MUCUS FROM CALF'S STOMACH INOCULATED INTO MILK AFTER EIGHT TRANSFERRINGS 116
29.—DIPLOSTREPTOCOCCUS FROM YOGHOURT. PURE CULTURE IN SKIM MILK 116
30.—PHOTO-MICROGRAPH OF PREPARATION MADE FROM YOGHOURT, SHOWING YEAST CELLS 118
31.—PHOTO-MICROGRAPH OF SMEAR FROM GREEK CURDLED MILK CALLED "GIAOURTI" 118
32.—PHOTO-MICROGRAPH OF SOURED MILK INOCULATED WITH A TABLET CONTAINING VIABLE AND PURE CULTURES OF _Bacillus bulgaricus_ 120
33.—PHOTO-MICROGRAPH OF MILK INOCULATED WITH A FERMENT TABLE IN WHICH _Bacillus bulgaricus_ IS NO LONGER VIABLE 120
34.—PHOTO-MICROGRAPH OF SMEAR OF CULTURE OF _Bacillus bulgaricus_ 122
35.—_Bacillus bulgaricus_, SHOWING THE CULTURES IN ENGLISH COW'S MILK 124