I'm no expert on the history or usage, but Googling about:
It looks like it may have been called ishidaki
(石抱), commonly translated as "pressing stone" technique. I usually associate the verb "daku" more with embracing or holding something -- unless that's another meaning I'm less familiar with. But common acceptance and diffusion of a loose translation would not surprise me there.
I also see one post so far (the link mentioned at the end) that says it may alternatively be called sorobanzeme
(算盤責). This, I would roughly render as [the victim] being wedged between the rungs of a soroban, or ridge shapes (below the legs) akin to those found on a mathematics abacus.
I suspect there are some kana missing at the end of those kanji compounds if you were to write them in a modern letter, but I'm not positive: Anyway, during the Edo period I guess they could (I want to say, probably would?) have just written the Chinese characters and left it at that? I haven't looked far into historical Japanese language too recently.
For an amusing graphic for overworked students, here's a modern alternative image from manga.
The text with it reads: "We're just getting started..."