I just came across the phrase そこはかとなく, which weblio translates as:
特にどこがどうと言うわけではないが、雰囲気として感じられる様子などを表す表現。
Expresses the idea of feeling something as a mood, and not for any particular reason.
This page proposes that the phrase originates from something like 其処は彼となく, that is, "in such a way that that thing there is not a certain person". This seems plausible, but my confusion was when I looked into the reading for the phrase.
It seems that the は is to be read literally as ha, and not as the particle は wa, which seems totally unexpected.
My question: Is は really read as ha in this phrase? And if so, is it actually the topic marker read in an unusual way, or is it something else entirely?