structure in OB winds is not random, but rather the result of CIRs. Exactly how CIR structures affect wind lines, X-rays, free-free emission and other wind diagnostics is, as yet, largely unexplored.

Support for program HST-GO-12218 was provided by NASA through a grant from the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 5-26555. We thank the referee for commenting on the manuscript.

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