Ice, quantities consumed in “low” breweries, 11
Illusions as to absence of foreign organisms, 36, 85, 92
Impregnations, spontaneous, 65, 66, 69, 73, 79
Impregnation, mode of (_penicillium glaucum_), 86
Impurity of ferments, source of experimental errors, 37 of yeast masked for a time, 220
Increase of yeast disproportionate to sugar used, 237
Infusions, nature of organisms in, 39
Infusoria, 35
Insoluble substances in wort, 386
Inverting constituent of yeast, 321, and footnote
Isolation of ferment, 77
