#Lecture Comprehension: Le volcan
hexed tangle
point d'exclamation => exclamation mark
This is a genitive construction. You are qualifying a noun using another noun.
In English, such a noun is called an attribute, and can basically be used like an adjective. In French, on the other hand, you have to use a preposition to achieve the same effect (à, de, en...), the choice being based on the relationship between the two nouns.
Here, "exclamation" is qualifying the purpose of "point", so "de" is used (with elision because it's followed by a vowel)
tall wave
Ohh, I see, merci
fleet cloak
It's a point of exclamation, if you will.