The action is snorting ().
_: When the priest heard this, his small eyes lit up,_
_: and he snorted two or three times in satisfaction._
See the Jisho entry for :
> _1\. to ring; to sound; to chime; to beat; **to snort (nose)** ; to snap (fingers); to crack (joints)_
>
> _2\. to be popular; to be esteemed; to be reputed_
>
> _3\. to state; to insist; to complain_
>
> _4\. to fart (loudly) Archaism_