A scar “by inoculation” on this 1809 Seaman’s Proof of Citizenship likely refers to an inoculation against smallpox.
Those with a knowledge of the fight to eradicate smallpox will remember that vaccines were around in 1809. How common it was for sailors to have been vaccinated during this time I don’t know.
Another interesting bit of information that can be gleaned from these records. Sometimes one doesn’t know what is in a set of records until one takes the time to actually browse the records.
If I have any ancestor or relative on whom I’m stuck and there’s even a sliver of a chance that he went to sea, these records should be accessed if for no other reason that one never knows what information they might contain in that “description.”