Madeira. craters in the.island, and* thaffe eruptfons had
“ taken place from, them: at various and .^ r ^ dtstep*
“ intervals. This was particularly manifest at a pbfce
‘“near the Brazen-head, where might easily bcT-Coujfcecf
c f l®va from a neighbouring
‘JjfaraÆwi T i e strata,7®r,.tóye*rof.:laya, WCtevaU distin«
« gnisled. frétai each' ether by the.following regular.
“ arrangement: first, the bottom part w.a% hard,;$olid
‘‘ la v à ij- sefentificalîy. termed, compact dava;; secondly,
“ «ver the layer o f compact lava,; lay a. layer èfyselfûkr
“ lava ; tàardly^:hext came t h e scorise,r partakihgvpfÆe
“ nature of pumice .stones ; .and,olastly, thfe vokdnic
“ ashes. ThekconAeruption layrarrangednk the same
“ order above the first; andnôPéiy other,rte the twelfth
“ leruptionv
“ A deeprexcavation-; furnished in one place an op-;
“ portuhityibf ©bservin^ithat thé, bottom: node,i.on
“ which t h e first l^rer o f ..compact kva rested, w fe :
“ chiefly ati iron; orfev composed of calx,, or mineral of
“ iron ; and. o f clay .• From which circumstances it was
“ inferred, that this rock had never been exposed' to
5 a* y high degree o fb e a t; otherwise the iron- would
% bkve-sbeeniiusölv and; b y its spécifie gravity, would
“ have descended tp; the lowest part, and'left the loose
“ d a y upon* the surface; and; also;-that the, facers'of
“ superincumbent lava had flowed from a.crater of a
“ date nfore recent than ,the formation o f the’ öre. It
would be difficult to conceive how these appearances Madeira.
b®\ïld' have sbéeïi 'produced»“ r.ka|fe the whokrisland,
Originfilly ; il^fenTormed by vpfoarf fire,: ahdthrown
tip from l%efcîttdftEieif the ©fee^n. Itcontains, radioed,
tadeh matter .‘which has* net pn de rgp h e,o or, afetleaSf,
rfe)eWS' nO^xSaïfostb'f, the' aCtiört- of fire. * * Besidè^ therein
te^^ahe'àdy meriiionkdV'1 quart?; .undbcomposedc; and
#ë#$#cómpact%as héén irrs'evcfab places fpundjîafta1
high hp’thc h'IM$&l,*
iff TJlie^hliih of the*tógheSt mouht&înssisf Madeira* hils
hardly raùyî#oIêâ0idP4ppéafknce.' The Mohds/elnyl--
lope'v frequently, their tops ; hnd from th e itodeSce n d
a # the ''Streams I and ri^ülets of the tsknd. Their
antiquity is marked by the^êep j chasms' or$ ghfphk
ilhey- have-formed, in their d4|3§eht$ betweeïpfflh
%1d|èsrgf thé % ék s,during the'fopg i-ap^ fbfiJtinih
dhey have f®éntinued tö-fiow. In theS'bedsVof
rivulets are found pebbles of vàridüs^sîzê# arrdHiürge
rounded napes’o f silex,' such as. are usuallyfound in
thé hèdsf óf many Sïmikrtorrents^iïi' the* Alps. The
is&ii, also, of the fields and pasturage »‘grounds’appears
exàctly the same ês those o f th # cöntfnentr,";whëre no
Vqleanic fire haS eVer^bééït-Süspected. It ^likewise
tórbe observed; thatfno-' lava 'óf S* glassy nature has
»been discovered in Madeir'af1'fibr any'‘Ç^tfedÈ1 phmicé
stoned !'eirdümstari'ces, '\vhfïfh «both' indicate,ythat*M!ô|
thevhigheèt" flégrée of heat httdhbdlhf Süffeïèd hère'r ;