Complex sentence: Hogue explains that the boy had chewed his father's tobacco and was given too much bismuth subnitrate as an antacid, causing a blue tinge; the carbonic acid component of the soda would relieve his stomach ache.
Split into simpler sentences: Hogue explains that the boy had chewed his father's tobacco and was given too much bismuth subnitrate as an antacid, causing the blue tinge. The carbonic acid component of the soda would relieve his stomach ache.