It is the 1914 edition of Our Wonder World. Although I have never read the text, I found it full of great, scientifically accurate pictures. I still have it, and when I want to know stuff I just look at the pictures and imagine what they're about. For instance, when I need to know anything about the solar system, I consult this illustration captioned, "Off for the planets!":
As you can see from this detail of the illustration, there were two people in the crop duster:
Solstice is taken from the Latin "Sol", meaning Sun, and "sistere", meaning to stand still. It means the day is much longer than the night because the sun seems to get stuck --except in countries closer to the North Pole where the sun just flies around in a circle and is still thought to be a comet. For Equinox, I had to consult a more modern authority, Norma, who said "Equus means horse. So equinox is when we all turn into horses?"
I disagreed: " Silly idea. You're neglecting "nox", obviously from the Latin "noxa", meaning toxic or dangerous."
"So," she said. "Twice a year we turn into very unpleasant horses."
I closed and reshelved Our Wonder World, satisfied the time to read its text has not yet come.