USS Siwash (SP-12) was an armed motorboat

Motorboat

A motorboat is a boat which is powered by an engine. Some motorboats are fitted with inboard engines, others have an outboard motor installed on the rear, containing the internal combustion engine, the gearbox and the propeller in one portable unit.An inboard/outboard contains a hybrid of a...

 that served in the United States Navy

United States Navy

The United States Navy is the naval warfare service branch of the United States Armed Forces and one of the seven uniformed services of the United States. The U.S. Navy is the largest in the world; its battle fleet tonnage is greater than that of the next 13 largest navies combined. The U.S...

 as a patrol vessel from 1917 to 1919.

Siwash was built in 1916 by the Gas Engine and Power Company at Morris Heights, New York

New York

New York is a state in the Northeastern region of the United States. It is the nation's third most populous state. New York is bordered by New Jersey and Pennsylvania to the south, and by Connecticut, Massachusetts and Vermont to the east...

, as a private motorboat of the same name. The U.S. Navy acquired her from her owner, C. A. Schieren of New York City

New York City

New York is the most populous city in the United States and the center of the New York Metropolitan Area, one of the most populous metropolitan areas in the world. New York exerts a significant impact upon global commerce, finance, media, art, fashion, research, technology, education, and...

, on 18 June 1917 for World War I

World War I

World War I , which was predominantly called the World War or the Great War from its occurrence until 1939, and the First World War or World War I thereafter, was a major war centred in Europe that began on 28 July 1914 and lasted until 11 November 1918...

 service. She was commissioned

Ship commissioning

Ship commissioning is the act or ceremony of placing a ship in active service, and may be regarded as a particular application of the general concepts and practices of project commissioning. The term is most commonly applied to the placing of a warship in active duty with its country's military...

 as USS Siwash (SP-12) on 18 August 1917.

Siwash patrolled in the 3rd Naval District in the New York City area until decommissioned

Ship decommissioning

To decommission a ship is to terminate her career in service in the armed forces of her nation. A somber occasion, it has little of the elaborate ceremony of ship commissioning, but carries significant tradition....

 on 10 May 1919. She was transferred to the United States Department of Commerce on 16 June 1919.