Page:De re metallica (1912).djvu/112

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70
BOOK III.


A vena cumulata has a "beginning," an "end," a "head," and a "tail," just as a vena profunda. Moreover, a vena cumulata, and likewise a vena dilatata, are often cut through by a transverse vena profunda.

Stringers (fibrae)[1], which are little veins, are classified into fibrae transversae, fibrae obliquae which cut the vein obliquely, fibrae sociae, fibrae dilatatae, and fibrae incumbentes. The fibra transversa crosses the vein; the fibra obligua crosses the vein obliquely; the fibra socta joins with the vein itself; the fibra dilatata, like the vena dilatata, penetrates through it; but the fibra dilatata, as well as the fibra profunda, is usually found associated with a vein.

The fibra incumbens does not descend as deeply into the earth as the other stringers, but lies on the vein, as it were, from the surface to the hangingwall or footwall, from which it is named Subdialis.[2]

In truth, as to direction, junctions, and divisions, the stringers are not different from the veins.

  1. It is possible that "veinlets" would be preferred by purists, but the word "stringer " has become fixed in the nomenclature of miners and we have adopted it. The old English term was "stringe," and appears in Edward Manlove's "Rhymed Chronicle," London, 1653; Pryce's, Mineralogia Cornubiensis, London, 1778, pp. 103 and 329; Mawe's "Mineralogy of Devonshire," London, 1802, p. 210, etc., etc.
  2. Subdialis. "In the open air." The Glossary gives the meaning as Ein tag klufft oder tag gehenge—a surface stringer.