260 Heaves of Metalliferous Veins. 



percent. 



Those heaved towards the greater angle 59*3 



smaller angle 12*0 



Of 77 lodes which are heaved by cross-courses — 



The tin lodes are 19-5 



... lodes yielding both tin and copper ores . . . . 41*5 



... copper lodes 39*0 



Of 3 1 lodes which are intersected by cross-courses without 

 being hearted — 



The tin lodes are . ■ 22*6 



... lodes yielding both tin and copper ores .... 29'0 



... copper lodes 48*4 



22 tin lodes are intersected by cross-courses, and of them — 



Those which are heaved are 68 # 2 



not heaved 31*8 



41 lodes in which tin and copper ores are mixed are inter- 

 sected by cross-courses, and of them — 



Those which are heaved are . 78*0 



not heaved 22*0 



45 copper lodes are intersected by cross-courses, of which 



Those which are heaved are 66" 7 



not heaved 33*3 



feet. 

 The average distance of all the heaves by cross-courses is 10*5 

 the heaves of tin lodes . . . . 12*6 

 the lodes yielding 



both tin and copper ores 14*1 



copper lodes. . . 6*1 

 The mean distance of heaves by cross-courses towards the 



right-hand is 12-3 



left-hand .... 7*1 

 greater angle . . . 9'3 

 smaller angle . . . 16*3 

 It is a remarkable but well-known fact, that in Cornwall 

 the extent of the heaves by flucans is much greater than of 

 those by cross-courses. It is also not unworthy of notice that 

 the flucans heave the copper lodes further than they do the 

 others, whilst the cross-courses heave them much less. The 

 right-hand are larger than the left-hand heaves, both by flu- 

 cans and cross-courses ; but, with the former, the heaves towards 

 the larger angle are greater than those towards the smaller 

 angle, whilst with the latter the heaves to the smaller are of 

 much greater extent than those to the larger angle. 



Morro Velho Gold Mines, Brazil, W. J. HENWOOD. 



December 7, 1843. 



