INDEX TO PART LV. 
Page. 
Absorption of light by eget 16 
Acidic eruptive rocks, 144 
Acidic unstratified rocks, 173 
Actinolite,: . : 60 
Actinolite schist, 232 
Age of greenstones, 236 
Albany pees 198 
Albite, 98 
Almandite, . 72 
Alteration of basic eruptive rocks, 149 
Alum, ‘ 3 . ‘ 126 
Amazon stone, 102 
Amethyst, ‘ 49 
Amorphous bod bodies, optical properties 
co) : - 10 
Amphibole, 60 
Amphibolite, 230 
Analcite, . 112 
Analysis of albite, 98 
andesite, 96 
$s anorthite, ‘ gI 
ee anorthite diabase, . 156 
a argillitic mica schist, 219 
ee beryl, : 69 
ae biotite, . 79 
ss chalcopyrite, . 33 
as chlorophyllite, 78 
ie chrysolite, 70 
es columbite, 122 
as danaite, 34 
ee diabantite, : 120 
as diorite—eruptive, . 161 
sé diorite—metamorphic, . 228 
“ galenite, . 28 
ie garnet, 73 
es hematite, . - 38 
es hornblende, . - 63, 64, 65 
ss infusorial earth, a bz 
# iolite, i Oe 
es labradorite, 93, 95 
ei magnetite, »  4l 
ee micaceous diabase, 153 
as mountain cork, 115 
VOL. Iv. 32 
Analysis of olivine, . 
te orthoclase, 
oi pargasite, 
we prochlorite, 
us pyroxene, . 
ae quartz porphyry, 
es sphalerite, 
ee staurolite, 
es tourmaline, 
es triphylite, 
ne zircon, 
Andalusite, ‘ : ‘ 
fs alteration to cyanite, 
ee mica schist, 
Andesite, : ‘ 
Andradite, : a 
Ankerite, a 
Annite, 
Anorthite, 
Anorthite diabase, 
Anthophyllite, 
Antrim granite, 
Apatite, : 
Argentiferous galena, . 
Argentine, . 
Argentite, 2 
Argillite, . c 
Argillitic mica schist, 
Arsenic (native), 
Arsenopyrite, . 
Asbestus, 
Augen gneiss, . 
Augite, 
oe associated with hornblende, 
‘© in quartz porphyry, 
optical properties of 
“© sienite, : 
Autunite, 
Azurite, 
“ce 
Barite, 
Basic diorite, 
