This Could be Isabella Clark Beale nee Ferguson's brotehr David.

Source: Maryland State Papers

MDHR 19999 Box 48 Item 127

The State of Maryland to David Ferguson Gentleman Greeting.

Be it known, that reposing especial trust and confiendence in your fidelity, courage, good conduct, and attachment to the liberties of America, you are by these presents constituted and appointed Second Lieutenant of Marines on Board the Gallery called the Conqueror

You are therefore carefully and dilligently to discharge the trust reposed in you, by disciplining all officers and soldiers under your command; and they are hereby strictly enjoined and requried to obey you as their Second Lieutenant

And you are to observe and follow all such orders and directions as you shall from time to time recedive, according to the laws and constitution of the state, and the rules and regulations, which under the authority thereof, are or may be established. This commission to be in force until lawfully revoked.

Given at Annapolis this Seventeenth day of June. Anno domini 1777.