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80

PEOF.

 T. 
 G. 
 B01TOEY 
 OST 
 TWO 
 TEAVEESES 
 OF 
 THE 
 

On

 arriving 
 at 
 that 
 point 
 we 
 spent 
 a 
 considerable 
 time 
 in 
 vainly 
 

endeavouring

 to 
 strike 
 the 
 northern 
 edge 
 of 
 this 
 massif, 
 thongh 
 we 
 

saw

 the 
 rock 
 at 
 a 
 distance 
 across 
 a 
 valley. 
 Our 
 failure 
 was, 
 I 
 believe, 
 

caused

 by 
 a 
 slight 
 misunderstanding 
 of 
 our 
 map, 
 which 
 was 
 on 
 a 
 

small

 scale 
 and 
 not 
 in 
 much 
 detail. 
 Thus 
 we 
 missed 
 the 
 only 
 

place

 where 
 the 
 massif, 
 as 
 I 
 now 
 

see,

 can, 
 without 
 much 
 trouble, 
 be 
 

reached

 from 
 the 
 highroad. 
 We 
 

saw,

 however, 
 some 
 scattered 
 frag- 
 

ments,

 which 
 were 
 mainly 
 gabbro, 
 as 
 

above

 described. 
 

Jurassic

 limestone, 
 often 
 dark 
 in 
 

colour,

 extends 
 to 
 the 
 commence- 
 

ment

 of 
 the 
 steeper 
 part 
 of 
 the 
 

descent

 towards 
 Italy 
 (fig. 
 3). 
 Here 
 

it

 has 
 a 
 high 
 dip, 
 75° 
 or 
 more 
 to 
 

the

 W.N.W. 
 Beneath 
 a 
 thick 
 con- 
 

spicuous

 mass 
 of 
 this 
 rock 
 comes 
 a 
 

calcareous

 deposit 
 of 
 uncertain 
 nature, 
 

not

 unlike 
 a 
 tufa 
 *, 
 to 
 which 
 succeeds 
 

a

 dull-green 
 serpentine, 
 rendered 
 very 
 

schistose

 by 
 crushing. 
 Its 
 rude 
 

cleavage

 - 
 structure 
 appears 
 to 
 be 
 

roughly

 parallel 
 with 
 the 
 bedding 
 of 
 

the

 dark 
 limestone. 
 To 
 th 
 e 
 serpentine, 
 

of

 which 
 there 
 is 
 a 
 rather 
 thick 
 mass, 
 

succeeds

 a 
 lead-coloured, 
 rather 
 cal- 
 

careous

 mica-schist, 
 also 
 intensely 
 

crushed,

 the 
 resulting 
 structure 
 being 
 

parallel

 with 
 that 
 in 
 the 
 serpentine. 
 

This

 much 
 resembles 
 some 
 members 
 

(when

 highly 
 crushed) 
 of 
 the 
 " 
 Tcalk- 
 

haltige

 grauer 
 ScJiiefer" 
 of 
 the 
 Central 
 

Alps.

 The 
 two 
 rocks 
 may 
 be 
 seen 
 

near

 together 
 : 
 but 
 in 
 the 
 neighbour- 
 

hood

 of 
 the 
 road 
 we 
 could 
 not 
 find 
 an 
 

actual

 junction. 
 Between 
 this 
 place 
 

and

 Cesanne, 
 we 
 saw 
 in 
 situ 
 only 
 

varieties

 of 
 this 
 crushed 
 mica-schist, 
 

and

 below 
 the 
 village 
 is 
 more 
 of 
 the 
 

same

 rock, 
 rather 
 darker 
 in 
 colour 
 

and

 somewhat 
 more 
 calcareous, 
 its 
 

dominant

 structure, 
 which 
 dips 
 to 
 the 
 

S.W.

 at 
 a 
 moderate 
 angle, 
 being 
 the 
 

result

 of 
 subsequent 
 pressure. 
 (Ap- 
 

pendix,

 p. 
 103.) 
 

Part

 of 
 the 
 ' 
 Gypse 
 et 
 carnegules 
 ' 
 (Trias) 
 of 
 Prof. 
 Lory's