Bookbinder's trade labels like Barclay's, found on the inside cover of some of his works, are considered a rarity among books printed in colonial America.
They maintain that the books containing binder's trade labels have largely gone unnoticed or unidentified and hope that more examples are yet to be found pending continued searches.
Because of limited resources, with virtually no patronage from royalty or wealth, with little access to superior sources of materials, along with the unstable and wavering economic and political factors present in the colonies, their work was generally of average quality compared to that of European bookbinders.
[12] In September and October 1771 ads advertising bookbinding by Barclay appeared for six consecutive weeks in Thomas' patriot newspaper, The Massachusetts Spy.
Likewise, all Sorts of Binding, Lettering, and Gilding done in the neatest and best manner...[13]Both Barclay and Taylor are known for their elaborately engraved trade labels which are found on the inside cover of their works.
[14] Consistent with Barclay's Loyalist sympathies, he bound works by William MacAlpine, Nathaniel Hurd and John Hicks who fled Boston for Halifax with the British army, all of whom had written in opposition to the prospect of American independence.
[15] When the American Revolutionary War broke out Barclay as a Loyalist assumed an active role by joining the Loyal North British Volunteers against the rebels in Boston.
When the British troops evacuated Boston in March 1776, he was forced to abandon his bookbinding wares and sailed for Nova Scotia, and soon thereafter to New York, where he remained until the end of the war; before leaving New York Barclay was honored by Sir Guy Carleton, and given a command over a company of Loyalist refugees bound for Shelburne, Nova Scotia, where he settled into a life of farming and ranching and was seldom involved in bookbinding.