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BOOK III.

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A —The " beginning.” B —The “ end.” C —The “ head.” D —The “ tail.”

E —Transverse vein.

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

Stringers ( fibrae ) 6 , which are little veins, are classified into fibrae trans-versae, fibrae obliquae which cut the vein obliquely, fibrae sociae,fibrae dilatatae, and fibrae incumbentes. The fibra transversa crossesthe vein ; the fibra obliqua crosses the vein obliquely ; the fibra soda joinswith the vein itself ; the fibra dilatata, like the vena dilatata, penetratesthrough it; but the fibra dilatata, as well as the fibra profunda, is usuallyfound associated with a vein.

The fibra incumbens does not descend as deeply into the earth as theother stringers, but lies on the vein, as it were, from the surface to thehangingwall or footwall, from which it is named Subdialis . 7

In truth, as to direction, junctions, and divisions, the stringers are notdifferent from the veins.

6 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 Englishterm was “ stringe,” and appears in Edward Manlove’s “ Rhymed Chronicle,” London,1653; Pryce’s, Mineralogia Cornubiensis, London, 1778, pp. 103 and 329; Mawe’s “ Mineralogyof Devonshire,” London, 1802, p. 210, etc., etc.

1Subdialis. “ In the open air.” The Glossary gives the meaning as Ein tag klufftoder tag gehenge —a surface stringer.