Snoopy’s second thought balloon looks like a speech balloon (and he sure has hygienic issues).
Charles Schulz did not originally have Snoopy “thinking” his dialogue. The speech balloons are consistent with that, since these are very early strips.The first time Snoopy “thought” anything was March 16, 1952, and in that strip he was thinking visually. (In fact, he still “speaks” in one panel.) His first “speech” in a thought bubble was a little over two months later, on May 27, 1952.
I initially read the first panel as “mud poodle.” Given that Snoopy is a dog, that made sense.
I wonder if Pig-Pen has to wash his hands because he “touched the dog”… that was one of my favorite Sunday strips from Peanuts… :P
I suspect this marks a transition from the old Snoopy (simply a dog) to the creature that walks and talks and sleeps on top of his doghouse.
Guess Sparky hadn’t learned about thought bubbles yet.
I have heard cats sigh so dogs can too.