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SCIENCE PROGRESS 



then for the exceptional richness of its blows of quartz, which 

 stood up in crags, owing to the wearing away of the softer slates. 

 The quartz "blows" seen on the surface were soon crushed, 

 and the miners followed them underground. This work led to 

 the disappointing discovery that the quartz veins, instead of 

 continuing to unknown depths, became thinner, and soon 

 pinched out. The quartz occurred in wedge-shaped bands, 

 scattered with such apparently inexplicable irregularity through 

 the slates, that it was thought they could only be found by 



S.R.2 



Fig. 3. — Saddle Reefs at Bendigo 



chance. Rich though the quartz often was, it would never repay 

 the dead work of haphazard blind-stabbing through the slates. 

 So the field was thought to be done. 



The yield, which averaged nearly 500,000 oz. a year up to 

 1855, and amounted to 527,407 oz. in 1857, fell fairly steadily to 

 under 200,000 oz. from 1877 to 1880, and down to 137,964 oz. 

 in 1890. 



But the miners found in time, that the quartz was not so 

 erratic in its distribution as had been thought. The wedges 

 were found to be the lower sides of arches of vein quartz, 

 which were always connected with arch-like foldings in the 

 country rocks. The lodes were therefore called "saddle reefs." 



