THE GEOLOGIST 
JULY, 1861. 
ON METALLIFEROUS SADDLES. 
By Dr. R. N. Rubidge, of Port Elizabeth, South Africa. 
In the number of your journal for October, 1860, I read with great 
interest a paper by Dr. Watson " On the Metalliferous Saddles of 
Derbyshire and Staffordshire." The Doctor says that, though well 
known to the miners, he believes these saddles have not hitherto been 
described by any geologist. If he will refer to the Journal of 
the Geol. Soc, 1857, p. 233, he will find a paper "On the 
Mines of Namaqualand," in which I think he will recognise 
a description of these deposits under the name of " metallic axes." 
With such modifications as the difference in the strata and their 
metallic contents requires, his description would nearly apply to what 
I said. 
The strata in which my axes occur are gneiss and gneiss-granite 
with occasional beds of magnesian and micaceous rock at Springbok 
Vontein and Concordia, and micaceous and calcareous rock, -with 
gneiss at Kodas. The saddles (a better name than mine) in all the 
productive mines were folds in the strata, with fissures of various 
sizes and directions intersecting them. The one was in some cases 
more abundant in the planes corresponding to the original bedding 
of the rock : this was strikingly the case at Concordia, where the 
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