But the work which probably made his “calling and election sure” was his masterly illustration of an article written by Mrs. Helen S. Conant, entitled “Birds and Plumage.” Gibson had suggested the article, furnishing the idea and proposing as a title “The Plumage of Fashion.” He did not secure the commission to write the text: his abilities as a writer had not been demonstrated, and he himself was diffident about them. But he received the order for sixteen illustrations, into which we may well believe he threw his whole strength. The initial design attracted marked attention and drew out unstinted praise. It was a full-page picture of a peacock’s feather. It gave the article instant success. The press was enthusiastic in commending it. The August number of “Harper’s Magazine” for 1878 may be said to have marked a new epoch in American illustration; and young Gibson’s work led all the rest. The reserved and refrigerated criticism of the “Nation” was relaxed almost to the point of enthusiasm: “The remarkable series of birds drawn on the block by Mr. William H. Gibson is more obviously than the imitations just mentioned the result of the engraver’s skill and unwearied patience. The cut of the peacock feather, for instance, which introduces the paper on ‘Birds and Plumage,’ must impress even the uninitiated with its rare and costly character, whether regarded as a design or as an engraving. Mr. Gibson has evidently studied his subjects with great care and succeeded in portraying them, both in action and in repose, in a graceful and life-like manner, with instructive accessories.” The “Christian Union,” always careful and conservative, said: “Upon this article, which has been a long time in preparation, the publishers have, it is understood, laid out an unprecedentedly large sum of money. Certainly Mr. Gibson’s graceful pencil has given them the worth of it. No better work, it is safe to say, has ever appeared in the pages of the magazine.” But best and most conclusive of all the words of praise which this drawing elicited, were those of Mr. Charles Eliot Norton, in a personal letter to the young artist: “CAMBRIDGE, _Nov. 8, 1878_.