Inactive Tutor answered 06/05/19
In this case, "scarce" is closer to "hardly" or "barely" than anything else. It suggests that the Time Traveler isn't thinking about stopping and is only thinking of "these new sensations" and not anything else.
It's being used as an adverb, so a modern writer might add an -ly ending ("scarcely"), but Wells' usage reflects the particular time and place he was writing.