Though scholars have long been familiar with Peacock's interesting statement concerning the strong influence exerted upon Shelley by certain novels of Charles Brockden Brown, no one has undertaken to define precisely the extent of Shelley's debt to the American novelist. Professor M. T. Solve in a recent article has ably analyzed the intellectual and spiritual kinship of the two men, and pointed out the general direction of the presumptive influence, but he notes no specific indebtedness beyond the borrowing of some details of gothic phraseology and the name Constantia. It is my present purpose to examine relevant passages from the works of Shelley in the light of Peacock's statement, with a view to more precise definition.