Ladder-climber / corporate ladder

[Paul McFedries]

I'm trying to find out when the phrase "ladder-climber" (an ambitious
employee) entered the language. The OED has the following from 1870:

The *ladder-climbers, who now direct the affairs of Paris.

The OED doesn't have "corporate ladder," but I've always assumeded
"ladder-climber" came from that phrase. Is there some other kind of
ladder that these Parisians would have been climbing? Does "ladder" have
a broader metaphorical sense of, say, something that one "climbs" to
move up in the (business/social/whatever) world?

Thanks.

Paul
wordspy.com