A matross was a soldier of artillery, who ranked next below a gunner.
The duty of a matross was to assist the gunners in loading, firing and sponging the guns. They were provided with firelocks, and marched with the store-wagons, acting as guards. In the United States Army, a matross ranked as a private of artillery.
The word (pronounced , ) is probably derived from French , 'sailor'.Britannica 1911 The OED states that the word is borrowed from the Dutch ('a sailor of the lowest rank'), and is cognate with similar terms in German, Danish and Swedish. Matross at Oxford English Dictionary
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