Mr. Ross was made a member of the Committee of Safety for Pennsylvania; vice president of the Constitutional Convention of 1776; colonel of the First Battalion of Associators for Lancaster County; and as a fitting climax, he signed the Declaration of Independence.
During his service as a member of the Continental Congress he was named on the committee with General George Washington and Robert Morris to prepare a design for a new flag. It was through his suggestion that the committee called on his niece, Betsy Ross, and with her help the beautiful flag of the United States was designed and adopted.
Ill health forced Colonel Ross to resign from Congress and on leaving office the citizens of Lancaster voted him a piece of silver to cost £150, which he declined to receive.
After varied and valuable labors in the service of the colonies and of Pennsylvania he was appointed a judge of the Court of Admiralty, as a minute of the Supreme Executive Council for March 1, 1779, records the following:
“Resolved, That the Honorable George Ross, Esquire, be commissioned Judge of the Admiralty of this State, under the Act of Assembly; that this Board highly approve the firmness and ability he has hitherto shown in the discharge of his said office.”
During his incumbency, which lasted but a brief period, he was regarded as learned and prompt, a happy combination.
Judge Ross probably knew the standing of every merchant in Philadelphia.
His house in Lancaster stood on the site of the present Court House, and his country home was a farm in what was then a suburb of Lancaster, now a part of the city, called in his honor, Rossmere.
He was interested in several iron furnaces, the most important of which was the Mary Ann furnace of York County. This was the first blast furnace west of the Susquehanna. His partners were George Stephenson, one of the first lawyers in York County, and William Thompson, the latter’s brother-in-law, later distinguished as a general in the Revolution. George Ross also owned Spring Forge III, also in York County, and he was a partner with George Taylor, of Easton, another signer of the Declaration of Independence, in a furnace in New Jersey called Bloomsbury Forge.
His half brother John Ross, was also much interested in the iron business, and seems to have been a rather picturesque character. He was an officer of the King, and Graydon says of him: “Mr. John Ross, who loved ease and Madeira much better than liberty and strife, declared for neutrality, saying, that let who would be king, he well knew that he would be a subject.”