xx 
rough spheroidal and globular masses of either granite,* slate,t 
elvan,t quartz,§ galena,|| copper-pyrites,7 or tin-ore,** “which 
are frequently enveloped in successive accretions, either of the 
same,*t}§ or of different,}+ substances. Moreover in masses 
of uniform composition, one extremity is sometimes of schistose 
structure, whilst the other is made up of successive hemispheroidal 
layers.tt In many cases, however, no aggregation of successive, 
concentric, layers seems to have taken place” since the spheroidal 
masses assumed their present forms.§§ Cavities (vughs), of 
larger or smaller dimensions, occur, in some part or other, of 
every lode; and beside these, the quartz of some veins contains 
microscopic cavities, which number “ upwards of a” thousand mil- 
lions in one cubic inch.|||| In their composition the lodes always 
partake the nature of the immediately contiguous rock ;4 4 and thus 
in the granite and elvan felspar prevails ;§[§ yet in both quartz is 
* Edmonds, Cornwall Geol: Trans: iii., p. 332. Carne, Ibid, iii., p. 
238. Henwood, Edin: New Phil: Journal, xxii., p. 166; Cornwall Geol: 
Trans: v., pp. 40, 183. Salmon, Quarterly Journal of the Geol: Society, 
XvVii., p. 518. e 
+ Carne, Phil: Trans: xevii., p. 293; Cornwall Geol: Trans: ii., p. 94. 
Henwood, Edin: New Phil: Journal, xxii., p. 166; Cornwall Geol: Trans: 
v., pp. 40, 183. De la Beche, Report, p. 322. Boase, Primary Geology, 
pa 115. 
+ Henwood, Edin: New Phil: Journal, xxii., p. 166; Cornwall Geol: 
Trans: v., pp. 38, 87, 183. 4 
§ De la Beche, Report, p. 322. Henwood, Cornwall Geol: Trans: p. 
183; Table vi. 
|| Ibid, viii., p. 703. 
q Ibid, v., p. 183. 
** Carne, Ibid, iv., p. 100. Honey Report of the Miners’ Association, 
1867, p. 55. 
++ Henwood, Cornwall Geol: Trans: v., p. 184. 
++ Carne, Phil: Trans: xevii., p. 293; Cornwall Geol: Trans: ii., p. 
94; iit. p. 100. Henwood, Edin: "New Phil: Journal, xxii., p. 166; Corn- 
wall Geol: Trans: v., p. 183. Salmon, Quarterly Journal of the Geol: So- 
ciety, Xvil., pp. 517-522. Henty, Report of the Miners’ Association, 1867, 
p. 55. 
§§ Sorby, Quarterly Journal of the Geol: Society, xiv,, p. 474. 
\||| Carew, Survey of Cornwall, £.10. Borlase, Natural History, p. 148. 
Carne, Cornwall Geol: Trans: iii., p. 80. Boase, Ibid, iv., p. 442. Fox, 
Reports of the Royal Corn: Pol: Society, iv., p. 85. Dela Beche, Report, 
p. 318. Henwood, Cornwall Geol: Trans: v., p. 190. Von Cotta, Ore- 
Deposits, p. 412. 
qq Jars, Voyages Métallurgiques, iii., p. 194. Carne, Cornwall Geol: 
Trans: ii., p. 88. Henwood, Ibid, v., pp. 186, 226; viii., pp. 675-680. Von 
Cotta, Ore-Deposits, p. 212. 
