I can't remember where I first came across it, but I know that I read at least one old SF story as a child which referred to "rocket tubes". I'm not asking for story identification. I know there were many stories that used the concept. I can tell this even without reading many such stories, because 1930s-50s SF pulp cover art (among other things) frequently depicts spaceships with clusters of tubular engines. Example of them being explicitly "tubes".
This doesn't match the real appearance of rocket nozzles. Where did this concept come from?
What exactly am I looking for? My assumption was that there was an influence other than those early examples of clustered solid rockets, and that influence was part of what I was looking for. That said, there was another aspect I was looking for.
I want to find the earliest appearance of this design in SF art or film, and the earliest appearance in written SF of rockets (not solid fuel) described as 'tubes'. It could be telling whether it appears first in writing or art.