While going through the Golden Age Comics archive, I noticed that apparently movies weren't the only form of entertainment that were silent when they started. Take a look at these panels from 1941's "Super Mystery Comics" and notice how the artist renders the sparse onomontoPOWia:
The big jagged-outline visual effects we've come to expect are already present (filled with yellow, usually), but the accompanying sound effects owe more to the craft of the letterer than the artist. In fact, I believe the letterer was responsible for filling in these elements, for many many years, which might explain their spartan appearance.
I also began to notice how rarely sound effects were used at all. You could almost guarantee a gun firing would get a "BANG" or "POW", but seldom anything else that wasn't very loud indeed in the real world. You can go for pages and pages without any onomontoPOWia at all, which to modern eyes is quite strange.
The medium progressed quickly, though, as you can see from this panel from 1947's "Cowpuncher":
The simple typographical black words are now more boldly drawn and filled with a dramatic red, slanting into the frame on the same trajectory of the bullet. Compare that to the earlier "Smacko" and you can see how much more effective the later treatment is.
Eventually, of course, onomontoPOWia would become so ubiquitous that you couldn't avoid it, crammed into almost every panel, and immortalized in the "Batman" television show with every punch or kick. I'm glad we've toned that down since then, incorporating the sense of hearing more fully into the page rather than making it awkward either by its absence or its omnipresence.
Going through these old comics is really amazing, I love seeing how the medium has evolved in the last fifty years. Do yourself a favor and head on over while you can still download them without having to register!