BOOK II 
VOLCANIC ACTION IN PEE - C AMBKIAN TIME 
CHAPTER Vm 
PKE-CAMBRIAN volcanoes 
, iv, Tl.. 
U Vol«.» : Vi. Tl,. Cl.»,.o«l ro»t Voto... 
Tut e«lv ..eol„.-ia,l hfatmy rf this gW*. lila> »“L !*»«? »*' 
be L°w., fm„ recavci. at o«ce a»uty a.bl 
to the lon<r series of revolutious which the surtace of the planet has uiit 
^„ e thisL'Uuevev parbaps co.ablate a. tbe lit.., Have bee., ... ^ 
™e obUterateJ. Even where they ..ill e,™t. tl.e.r ‘““'"S ^ 
» doabttal that, i., tryius to interpret .t, we hnd 
feel o.,.«lve, to be gropi.ig, 0 . it were, ... the d„„..es. » " 
legend, rather tha.. working in the light ol trustworthy and 
ehronieles. These pri.aeval reeo.-d. have been n.ore 1“‘* f ' ^ 
of soilnlons study during the last twenty years ..11 over lt“ ‘ f 
Aineriew A eertain a.uonnt of progre* 
made. But the problems they still pre»>nt tor solution are nu M.on and 
obscure. Fortunately, with ted try concern 
treirriltttient r^^^^^^ .» .he ...story o. pri.nev.l volcanic 
“‘Tihe earliest ,.nd least dehni.e division of the 
variou. na„.es have been applied. Son.e write.., believing that ‘ ™ 1* ^ 
preceded the first appearance of plants or annuals upon the B“»; “ 
Lined it Asoic-the lifeless age of s^ologioal history. But the ateuee^ol 
any hitherto detected trace of organic existence among le p ,. 
.As cannot be held to prove that these reeks we.e tormed belore 
