Mystery steel bar joist - T top chord

[kareng]

Can anyone identify this bar joist (see attached photo)? Unknown build-date. T shaped top chord and 5/8" diameter bars for the bottom chord. Span is 16' and depth is 10", spacing is 2'-6" supporting roof. I can't seem to find any info on it.

 

[SlideRuleEra]

Possibly Macomber. See this link:

http://www.eng-tips.com/viewthread.cfm?qid=372796

http://www.SlideRuleEra.net

http://www.VacuumTubeEra.net